EN 1870, Safety of woodworking machines – Circular sawing machines consists of the following parts: — Part 1: Circular saw benches with and without sliding table, dimension saws and bui
General
The machine shall comply with the safety requirements and/or protective measures of this clause
The machine will be designed in accordance with EN ISO 12100:2010, specifically addressing hazards that are relevant but not significant, such as sharp edges, which are not covered in this document.
For guidance in connection with risk reduction by design, see EN ISO 12100:2010, 6.2, and for safeguarding measures, see EN ISO 12100:2010, 6.3.
Controls
Safety and reliability of control systems
A safety-related control system encompasses everything from the initial manual control or position detector to the input of the final actuator, such as a motor The safety-related components of this machine's control system must address specific functions and meet at least the performance level (PL) requirements outlined in EN ISO 13849-1:2008.
— starting and restarting: PL = c (see 5.2.3);
— moveable interlocked guards: PL = c (see 5.2.3, 5.3.7);
— moveable interlocked guards with guard locking: PL = c (see 5.2.3 and 5.3.7);
— interlocking of the cutting stroke with saw-blade rotation and work-piece clamping: PL = c (see 5.2.3);
— the initiation of the braking system: PL = b (see 5.2.4, 5.2.5 and 5.3.4);
— the two-hand control device: PL = c (see 5.2.3 and 5.3.7);
— on semi-automatic machines interlocking of self closing power operated guards with the position of the saw unit: PL = c (see 5.3.7.1);
— the active opto-electronic protective devices (light barriers): PL = c (see 5.3.7.4);
— the pressure sensitive mats: PL = c (see 5.3.7.4);
— the mechanically actuated trip devices (trip bar): PL = c (see 5.3.7.4);
— the work-piece clamping: PL = c (see 5.3.8)
Time delay devices shall be PL = c in accordance with the requirements of EN ISO 13849-1:2008
Verification: By checking the relevant drawings and/or circuit diagrams and inspection of the machine
NOTE For components characteristics the information from the component supplier can be useful.
Position of controls
The primary electrical controls for initiating the saw-blade spindle drive motor and for standard stopping must be situated on the machine, either beneath the work-piece support or on a control panel that is strategically positioned.
1) behind and above the fence; and
2) within 850 mm measured horizontally from the front edge of the work-piece support; and
3) at a maximum height of 1 600 mm from the floor level
The two-hand control device for managing the cutting stroke must be positioned at the front of the machine, within 1.0 m of the cutting line when aligned at 90° to the fence Additionally, it should be located below the workpiece support and have a minimum height of 750 mm above the floor level.
Where the control for the clamps is separate from the two-hand control device it shall be within 400 mm measured horizontally to the two hand control device
For the positioning of the emergency stops see 5.2.5
Verification: By checking the relevant drawings, measurement and inspection of the machine.
Starting
Before operating or reactivating the machine, it is essential to ensure that all safety measures are in place and functioning properly This is accomplished through the interlocking systems outlined in section 5.3.7 The machine can only be started or restarted by using the designated start control device.
The initiation of the cutting stroke shall only be possible after saw-blade rotation and work-piece clamping have been initiated
The saw unit cutting stroke shall be controlled by a two-hand control device of at least type III B in accordance with the requirements of EN 574:1996+A1:2008
All reset controls shall be located outside protected areas and not reachable when standing inside a protected area
For electrically started machines see EN 60204-1:2006, 9.2.5.2 The exceptions described in
The safety related part of the control systems (also see 5.2.1) for starting and the interlocking arrangements shall be at least PL = c in accordance with the requirements of EN ISO 13849-1:2008
Verification: By checking the relevant drawings and/or circuit diagrams, measurement, inspection and relevant functional testing of the machine.
Normal stopping
The machine shall be fitted with a stop control system, which when actuated shall disconnect power from all machine actuators unless STO is used and actuate the brake (if provided)
For normal stopping of PDS(SR) (power drive system, safety related) see EN 61800-5-2:2007, 4.2.2.2 “safe torque off (STO)” and 4.2.2.3 “safe stop 1 (SS1)”
The stop control must comply with category 1 as per EN 60204-1:2006, 9.2.2 Upon activation, the stopping sequence should begin with the return stroke of the saw unit, followed by the removal of power to the work-piece clamping Next, power to the saw spindle drive motor should be cut, and the brake should be initiated if installed Finally, once the braking sequence is complete, power to the brake should be disconnected if an electrical brake is in place.
The stopping sequence must be fulfilled within the control systems When utilizing a time delay device, it is essential that the time delay is no less than the maximum run-down time The time delay can either be fixed or, if adjustable, the adjustment mechanism must be sealed.
The safety related part of the control systems (also see 5.2.1) for normal stopping shall be at least PL = c in accordance with the requirements of EN ISO 13849-1:2008
Verification: By checking the relevant drawings and/or circuit diagrams, inspection and relevant functional testing of the machine.
Emergency stop
The requirements of EN ISO 13850:2008 apply and in addition:
The machine shall be fitted with an emergency stop control system which shall conform to the requirements of
EN 60204-1:2006, 9.2.5.4 and 10.7 However, the requirements of EN 60204-1:2006 do not apply The emergency stop control device shall be at any time of self latching type
For emergency stop of PDS(SR), see EN 61800-5-2:2007, 4.2.2.2 “safe torque off (STO)” and 4.2.2.3 “safe stop 1 (SS1)”
Emergency stops must be strategically placed based on machine size, including locations within 1.0 m of both the loading and unloading positions, at the main control panel, within 500 mm of any two-hand control device (if applicable), and within 3.0 m of the saw unit.
A single emergency stop can be positioned to fulfil more than one of these requirements
When actuated the emergency stop shall disconnect power from all machine actuators and actuate the brake (if provided)
The emergency stop control must comply with category 1 as per EN 60204-1:2006, 9.2.2 Upon activation, the stopping sequence should begin with the return stroke of the saw unit, followed by cutting power to the saw spindle drive motor and engaging the brake if available Once the braking sequence is finished, power to the brake should be cut if an electrical brake is installed.
The stopping sequence must be fulfilled within the control systems When utilizing a time delay device, it is essential that the time delay is no less than the maximum run-down time Additionally, the time delay can either be fixed or the adjustment mechanism should be sealed.
The safety related part of the control systems (also see 5.2.1) for the emergency stop shall be at least PL = c in accordance with the requirements of EN ISO 13849-1:2008
Verification: By checking relevant drawings and/or circuit diagrams, measurement, inspection and relevant functional testing of the machine.
Integrated feed
The integrated feed of the work-piece positioning mechanism shall only operate when the saw unit is in its rest position
For the integrated feed of the saw unit, see 5.2.3
Verification: By checking relevant drawings and/or circuit diagrams, inspection and relevant functional testing of the machine.
Failure of the power supply
According to EN 60204-1:2006, sections 7.5 paragraphs 1 and 3, electrically driven machines must be designed to prevent automatic restart following a supply interruption once the voltage is restored.
In case of a loss of pneumatic or hydraulic pressure, it is essential to maintain the clamping of the workpiece until the saw-blade begins its return stroke To ensure this requirement is met, non-return valves should be installed on the actuating cylinders.
The automatic restart of the machine shall be prevented after restoration of the pneumatic or hydraulic energy
Verification: By checking the relevant drawings and/or circuit diagrams, inspection and relevant functional testing of the machine.
Failure of the control circuits
The requirements of EN 1037:1995+A1:2008 apply and in addition:
Control circuits must be designed to ensure that any circuit interruption, such as a broken wire or ruptured pipe, does not compromise safety functions, preventing issues like unintended machine starts or loss of workpiece clamping Compliance with standards EN 60204-1:2006, EN ISO 4413:2010, and EN ISO 4414:2010 is essential.
Verification: By checking the relevant drawings and/or circuit diagrams, inspection and relevant functional testing on the machine.
Protection against mechanical hazards
Stability
It shall be possible to fix stationary machines to a suitable stable structure, e.g floor Facilities for fixing are, e.g fixing holes in the machine frame (also see 6.3)
Verification: By checking relevant drawings, inspection and relevant functional testing of the machine.
Risk of break up during operation
Guards for the saw-blade must be constructed from either steel with a minimum ultimate tensile strength of 350 N/mm² and a wall thickness of at least 1.5 mm, or from a light alloy that meets the specifications outlined in Table 2.
Table 2 — Light alloy saw-blade guard thickness and tensile strength
Polycarbonate with a minimum wall thickness of 3 mm or other approved plastic materials, as specified in Annex B, is acceptable Additionally, cast iron must have an ultimate tensile strength of at least 200 N/mm² and a wall thickness of no less than 5 mm.
Verification involves examining the relevant drawings and measurements for plastic materials that possess characteristics differing from those specified for polycarbonate This is achieved by conducting the test outlined in Annex B and performing inspections on the machine.
NOTE For the ultimate tensile strength a confirmation from the manufacturer of the material can be useful.
Tool holder and tool design
The requirements of EN 847-1:2013 apply and in addition:
To safely change the saw blade, a spindle holding device must be used to keep the spindle stationary This can be achieved with a double spanner arrangement or by inserting a locking bar through the spindle If a locking bar is utilized, it must have a minimum diameter of 8 mm and be constructed from steel with an ultimate tensile strength of at least 350 N/mm².
Locking bars shall prevent the spindle from rotating if the spindle drive motor is inadvertently switched on
Verification involves examining the relevant drawings and conducting inspections, measurements, and functional tests of the machine For machines equipped with locking bars, an alternative test is performed: after starting the spindle drive motor with the locking bar in position, the spindle should remain stationary and show no signs of deformation.
NOTE For the ultimate tensile strength a confirmation from the manufacturer of the material can be useful
Saw flanges (or in the case of a flush mounted saw-blade - a flange) shall be provided
For saw-blades with a diameter of 450 mm or less, the diameter of both flanges, or the flange for flush mounting, must be at least one-fourth of the diameter of the largest saw-blade that the machine is designed to accommodate.
For saw-blades with a diameter > 450 mm, the diameter of the flanges shall be at least D/6, but not less than
Flanges, excluding those designed for flush mounted saw-blades, must have an outer clamping surface that is a minimum of 5 mm wide and recessed towards the center.
Where two flanges are provided, both outside diameters shall be within a tolerance of ± 1 mm
To prevent the saw-blade from loosening during start-up, operation, or braking, it is essential to implement precautions such as establishing a secure connection between the spindle and the saw-blade or ensuring a firm attachment between the front saw flange and the saw spindle.
Saw spindles shall be manufactured in accordance with the tolerances given in Annex A
Verification: By checking the relevant drawings, measurement and inspection of the machine
Braking
Semi-automatic machines must be equipped with an automatic brake for the saw spindle if the un-braked run-down time exceeds 10 seconds The braked run-down time should be under 10 seconds, or if the run-up time exceeds 10 seconds, it must be less than the run-up time, but it should not exceed 30 seconds in any case.
NOTE 1 In the case of failure of power supply this run-down time may be exceeded
A PLr of at least c for the braking function shall be achieved
The braking torque shall not be applied directly to the saw blade itself or the saw blade flange(s)
Where a spring operated mechanical brake or any other type of brake not using electronic components is fitted the last paragraph of EN 60204-1:2006, 9.3.4 does not apply (see 6.3)
For electrical braking, reverse current injection braking shall not be used
When an electrical brake with an electronic control system is installed, its control system must meet a minimum performance level (PL = b) and be designed in category 2 according to EN ISO 13849-1:2008, with the exception that the test rate requirement specified in section 4.5.4 of the standard is not applicable Additionally, the safety-related components of the braking control system should undergo periodic testing, such as monitoring the braked run-down time, using feedback from either the encoder on the spindle motor or by measuring the residual current in the motor's power wires.
The test must be independent of the primary braking control system or include an internal watchdog function It should also operate independently of the operator's intentions and be conducted at every spindle stop.
Where the test result is negative more than three times in succession, it shall not be possible to operate the machine A negative test result shall be indicated
The diagnostic coverage (DCavg) shall be ≥ 60 %
See EN ISO 13849-1:2008, Annex E for DC estimation
A simple electronic brake, utilizing basic electronic components such as rectifiers, transistors, triacs, diodes, resistors, and thyristors, can be classified as PL = b and designed in category 1, adhering to the specified requirements.
EN ISO 13849-1:2008 if the “mean time to a dangerous failure” (MTTFd) according to EN ISO 13849-1:2008, Table 5 reaches a value of “high” (at least 30 years)
NOTE 2 Complex electronic components like, e.g microprocessors or PLCs cannot be considered as well tried under the scope of EN ISO 13849-1:2008 and do therefore not fulfil the requirements of category 1
To calculate the probability of a dangerous failure for a simple electronic brake component lacking fault detection and testing capabilities, one can utilize the procedure outlined in EN ISO 13849-1:2008, Annex D.
Verification involves reviewing the relevant drawings and circuit diagrams, inspecting the machine, and conducting functional tests To determine the un-braked and braked run-down times, the applicable tests outlined in Annex C should be performed.
Devices to minimise the possibility or the effect of ejection
The direction of the rotation of the saw-blade shall be such, that the cutting force is directed against the fence
Verification: By checking the relevant drawings and/or circuit diagrams, inspection and relevant functional testing of the machine.
Work-piece supports and guides
The machine must include a work-piece support that meets specific criteria: it should extend at least 250 mm on either side of the cutting area, and the width must ensure that the front edge of the largest saw-blade does not extend beyond the support when the saw unit is fully advanced Additionally, the support within the cutting area must be constructed from wood, wood-based materials, plastic, or light alloys, and there should be no table rollers present within 250 mm of the cutting area.
Verification: By checking relevant drawings, inspection, measurement and relevant functional testing of the machine
1 work-piece support (machine table)
2 saw-blade (adjusted to maximum pivoting and canting)
B width of the work-piece support Α maximum pivoting angle
Figure 3 — Dimensions of work-piece support (machine table)
The machine must feature a vertical work-piece guide, serving as a fence on both sides of the cutting line, with specific requirements: it should be perpendicular to the non-pivoted saw unit and fixed in place to prevent the saw-blade from extending beyond the fence when at rest Additionally, considering the saw unit's ability to rotate for angled cuts, the section of the fence within 10 mm of the cutting line must be constructed from materials such as wood, plastic, or light alloy Furthermore, the fence's height should be at least 50% of the maximum cutting depth the machine is designed for, with an exception for a passage area for the saw blade, which must not be less than 60 mm.
Verification: By checking relevant drawings, inspection, measurement and relevant functional testing of the machine.
Prevention of access to moving parts
5.3.7.1 Guarding of the saw-blade and saw unit
Access to the non-cutting area of the saw-blade shall be prevented by a fixed guard extending to the central axis of the saw spindle
When users need to remove fixed guards for maintenance, the fixing systems must stay attached to either the guards or the machinery This can be achieved using un-losable screws, as outlined in section 6.3 x).
For safe saw-blade changing, a movable guard must be hinged to the fixed guard and interlocked with the spindle drive motor Alternatively, a fixed guard can be used, which requires a tool for removal and ensures that its fixings remain attached to the machine, in compliance with EN 953:1997+A1:2009, 7.2 It is essential that the guard cannot stay in place without its fixings.
To ensure safety when the saw unit is at rest, access to the cutting area of the saw-blade must be restricted This can be achieved through the use of fixed guards that remain attached to the machinery during maintenance, utilizing un-losable screws for secure fixing Additionally, any openings in these fixed guards should be designed to maintain the required safety distances.
EN ISO 13857:2008, Table 4 are met; or b) self closing power operated guards; or c) a combination of fixed guards and self closing power operated guards
Where self closing power operated guards are fitted they shall be interlocked with the position of the saw unit
To ensure safety, fixed guards must prevent direct access to any crushing or shearing hazards created by the saw unit's return stroke These guards should be designed to comply with the safety distances specified in EN ISO 13857:2008, Table 4.
The saw unit's cutting stroke must be managed by a two-hand control device, as specified in section 5.2.3 Upon release of this control, the saw unit is required to return to its rest position within 1.5 seconds.
The safety aspect of control systems, particularly for two-hand control and interlocking functions, must meet a minimum Performance Level (PL) of c, as specified by EN ISO 13849-1:2008.
Verification: By checking relevant drawings and/or circuit diagrams, inspection, measurement and relevant functional testing of the machine
5.3.7.2 Guarding of work-piece positioning mechanisms
Access to the hazardous areas of the work-piece positioning mechanism, such as those with crushing or shearing risks, must be restricted through the use of either a fixed guard or a movable interlocked guard with locking features, except in designated loading and unloading zones.
When users need to demount fixed guards for maintenance, the fixing systems must stay attached to either the guards or the machinery This can be achieved using un-losable screws, as outlined in section 6.3 x).
In loading and unloading areas, it is crucial to avoid access to points with impact hazards (feed speed ≥ 25 m min⁻¹) and drawing or shearing hazards This can be achieved by implementing fixed guards that remain attached to the machinery during maintenance or cleaning, using un-losable screws, or by utilizing movable interlocked guards equipped with guard locking mechanisms.
To ensure safety in accordance with EN 1088:1995+A2:2008, Annex N, any openings in guards must meet the safety distances specified in EN ISO 13857:2008, Table 4 Acceptable safety measures include pressure-sensitive mats that comply with EN ISO 13856-1:2013, which must be interlocked with dangerous movements and effective over a horizontal distance of at least 1.3 m from the nearest impact or shearing point Alternatively, an active opto-electronic protective device (light barrier) must adhere to CLC/TS 61496-2:2006 standards, positioned at least 1.3 m away from the nearest danger, with two horizontal beams set at 400 mm and 900 mm from the floor A combination of these safety measures is also permissible.
To prevent access to drawing in or shearing points at the in-feed opening of fixed or movable guards, measures outlined in 5.3.7.2 a) to d) must be implemented, or alternatively, a trip bar should be used in compliance with EN ISO 13856-2:2013.
A trip bar must be positioned above the in-feed opening and adhere to specific requirements: it should halt the machine's operation before a hand, resting on the workpiece and moving at the maximum designed speed, can reach any impact, drawing-in, or shearing point The trip bar's width must match or exceed that of the in-feed opening, and its bottom edge should be no more than 25 mm above the workpiece surface, with adjustable height to accommodate different workpieces, either automatically or manually Additionally, the trip bar must not pose a trapping hazard.
If a work-piece positioning device includes clamping and crushing hazards that are not mitigated by the measures outlined in section 5.3.7.2 a) to d), then it is essential to implement the preventive measures specified in section 5.3.8.
The safety components of control systems for pressure-sensitive mats, active optoelectronic protective devices, trip bars, and interlocking systems with guard locking functions must achieve a minimum performance level of PL = c, as specified by EN ISO 13849-1:2008.
Verification: By checking the relevant drawings and/or circuit diagrams, inspection, measurement and relevant functional testing of the machine
To ensure safety where powered roller tables are installed at machine in-feed and out-feed points, it is essential to prevent access to drawing-in points between the powered rollers and fixed components This can be achieved by either filling in the drawing-in points as specified in Figure 4 or by using an active opto-electronic protective device, such as a light beam, that complies with CLC/TS 61496-2:2006 This device must be interlocked with the dangerous movement and positioned at least 1.3 meters horizontally from the nearest drawing-in point, featuring a minimum of two horizontal beams—one located 400 mm from the floor and another at 900 mm.
Clamping devices
Power operated work-piece clamping shall be provided on all machines
The clamping devices shall be so positioned that there are no table rollers beneath the clamps
To prevent crushing hazards not addressed by previous measures, several methods can be implemented: a) utilize a two-stage clamping system with an initial clamping force of 50 N or less, followed by full force activated manually; b) employ a manually adjustable device to reduce the clamp/work-piece gap to 6 mm or less, with a stroke limitation of 10 mm; c) restrict the clamp closing speed to 10 mm/s or less; or d) install a guard fixed to the clamping device to minimize the gap between the work-piece and the guard to 6 mm or less, ensuring the clamp extends no more than 6 mm outside the guard.
The safety components of the control systems for monitoring the initial clamping force and regulating the clamp closing speed must achieve a performance level of at least PL = c, in compliance with EN ISO 13849-1:2008 standards.
Verification: By checking relevant drawings and/or circuit diagrams, inspection, measurement and relevant functional testing of the machine.
Protection against non-mechanical hazards
Fire
To minimise fire hazards, the requirements in 5.4.3 and 5.4.4 shall be met Also see 6.3
Verification: By checking relevant drawings, inspection, measurement and relevant functional testing of the machine.
Noise
5.4.2.1 Noise reduction at the design stage
When designing machinery the information and technical measures to control noise at source given in
EN ISO 11688-1:2009 shall be taken into account The most significant noise source is the rotating saw-blade
Operating conditions for noise measurement shall comply with the requirements of ISO 7960:1995, Annex N
Mounting and operating conditions of the machine shall be identical for the determination of emission sound pressure levels at the work station and sound power levels
For machines not subject to the requirements of ISO 7960:1995, Annex N, such as those with varying spindle speeds and saw-blade diameters, the specific operating conditions must be clearly outlined in the test report.
Sound power levels must be measured using the enveloping surface method outlined in EN ISO 3746:2010, with specific modifications: the environmental indicator K 2A should not exceed 4 dB, and the sound pressure level difference between the background and the machine at each point must be at least 6 dB, as detailed in the correction formula of EN ISO 3746:2010, 8.3.3, Formula (12) Measurements should be taken at a parallelepiped surface 1 m from the reference surface, and if the distance to an auxiliary unit is less than 2 m, it must be included in the reference surface The test method's accuracy should be within 3 dB, and a total of 9 microphone positions are required, following ISO 7960:1995, Annex N.
Alternatively, where the facilities exist and the measurement method applies to the machine type sound power levels may also be measured according to a method with higher precision, i.e EN ISO 3743-1:2010,
EN ISO 3743-2:2009, EN ISO 3744:2010 and EN ISO 3745:2012 without the preceding modifications
For determination of emission sound power level by the sound intensity method, use EN ISO 9614-1:2009 (subject to agreement between the supplier and the purchaser)
Emission sound pressure levels at the workstation shall be measured in accordance with the requirements of
The modifications to EN ISO 11202:2010 include that the environmental indicator K 2A and the local environmental factor K 3A must not exceed 4 dB Additionally, the difference between the background emission sound pressure level and the workstation sound pressure level should be at least 6 dB, as specified in section 6.4.1 of EN ISO 11202:2010, accuracy grade 2 (engineering) Furthermore, the correction for the local environmental factor K 3A should be calculated according to the requirements of EN ISO 11204:2010, A.2, with the reference limited to EN ISO 3746:2010, rather than the method outlined in Annex A of EN ISO 11202:2010.
EN ISO 3743-1:2010 or EN ISO 3743-2:2009 or EN ISO 3744:2010 or EN ISO 3745:2012 where one of these standards has been used as the measuring method
For noise declaration the requirements of 6.3 s) apply
Emission of chips and dust
To ensure efficient operation, the machine must be equipped with outlets for the extraction of chips and dust, allowing it to connect to a dedicated chip and dust collection system.
The opening of the capture device shall be large enough to capture the chips and dust projected
NOTE 1 The size of the opening of the capture device depends on the emission pattern and the distance between the emission source and the opening of the capture device
The design of the capture device must focus on minimizing pressure drop and preventing material buildup by avoiding abrupt changes in the direction of extracted chips and dust, as well as eliminating sharp angles and obstacles that could lead to the accumulation of chips and dust.
To ensure efficient operation, the transfer of chips and dust between the capture device and the CADES (chip and dust extraction system) must adhere to specific requirements This is particularly important for flexible connections in moving units, as it helps minimize pressure drop and prevents material buildup.
The design of hoods, ducts, and baffles must ensure that chips and dust are effectively conveyed to the collection system, utilizing a calculated conveying velocity for the extracted air within the duct.
20 m s −1 for dry chips and 28 m s −1 for wet chips (moisture content 18 % or above)
The pressure drop between the inlet of all capture devices and the connection to the CADES should be maximum 1 500 Pa (for the nominal air flow rate)
NOTE 2 A low dust emission can be expected if the air flow rate ≥ 800 m 3 h −1 is ensured
Verification: By checking of drawings, visual inspection and the following procedure:
— Measure the pressure drop at the chosen air flow rate by measurement under the condition given for noise measurement in the relevant C-standard or ISO 7960:1995
To measure noise levels according to the relevant C-standard or ISO 7960:1995, operate the machine without processing a workpiece and ensure the CADES is disconnected Verify that the machine generates an airflow from the capture device's inlet(s) to the connection outlet(s) to the CADES by using smoke at the connection outlet(s).
NOTE 3 For measurement of chip and dust extraction system performance two standardized methods are useful: concentration method (EN 1093–9:1998+A1:2008) and index method (EN 1093–11:2001+A1:2008).
Electricity
With the exception of 6.3, the requirements of EN 60204-1:2006 apply unless stated otherwise in this document
See EN 60204-1:2006, 6.2 for the prevention of electric shock due to direct contact and EN 60204-1:2006, Clause 7 for protection against short circuits and overloading
To safeguard individuals from electrical shock caused by indirect contact, it is essential to implement automatic isolation of the machine's electrical power supply This can be achieved through the activation of a protective device installed by the user in the power line of the machine, as detailed in the manufacturer's instruction handbook.
The degree of protection for electrical components shall be as follows:
29 a) for electrical controlgear, at least IP 65 in accordance with the requirements of EN 60529:1991 and
EN 60529:1991/A1:2000; b) for three phase motors, at least IP 5X in accordance with the requirements of EN 60529:1991 and
In accordance with EN 60204-1:2006, 18.2 and 18.6 the test 1 for the continuity of the protective bonding circuit and functional tests apply
Verification: By checking the relevant drawings and/or circuit diagrams, inspection of the machine and relevant tests (specified in EN 60204-1:2006, test 1 of 18.2 and 18.6)
NOTE For electrical components characteristics the information from the electrical component supplier can be useful.
Ergonomics and handling
The requirements of EN 614-1:2006+A1:2009 shall apply and in addition:
The machine and its controls shall be designed according to ergonomic principles in accordance with
EN 1005-4:2005+A1:2008 for work posture which is not fatiguing
The positioning, marking and illumination (if necessary) of control devices, and facilities for materials and tool set handling shall be in accordance with ergonomic principles in accordance with EN 894-1:1997+A1:2008,
Tanks containing compressed air drainers and oilers shall be placed or oriented in such a way that the filler and drain pipes can be easily reached
Machine components weighing over 25 kg must be equipped with appropriate attachments for lifting devices, such as lugs, strategically placed to prevent overturning, falling, or uncontrolled movement during transport, assembly, disassembly, decommissioning, and scrapping.
If the machine is fitted with a movable control panel, this panel shall be fitted with a facility to move it in the desired position
If graphical symbols related to the operation of actuators are used, they shall be in accordance with Table A.1 of EN 61310-1:2008
Further guidance is given in EN 60204-1:2006, EN 614-1:2006+A1:2009 and EN 614-2:2000+A1:2009
The height of the work-piece support shall be between 850 mm and 950 mm above the floor level
Verification: By checking the relevant drawings, measurement and inspection of the machine.
Pneumatic
Hydraulic
Electromagnetic compatibility
The machine shall have sufficient immunity to electromagnetic disturbances to enable it to operate correctly in accordance with EN 60439-1:1999, EN 60439-1:1999/A1:2004, EN 50370-1:2005 and EN 50370-2:2003
Machines that use CE-marked electrical components, when installed according to the manufacturers' guidelines, are typically safeguarded against external electromagnetic interference.
Verification: By checking the relevant drawings and/or circuit diagrams and inspection of the machine.
Laser
If the machine is fitted with a laser to indicate the cutting line, the laser shall be of category 2, 2M or a lower risk category in accordance with the requirements of EN 60825-1:2007
Direct eye contact with the nominal ocular hazard area shall be prevented, e.g by use of an extension piece to maintain a safe distance
The laser shall be fitted to the machine so that warnings on the laser itself remain visible
All guidelines from the laser manufacturer regarding installation and usage must be adhered to The laser's operating instructions should be clearly outlined in the instruction manual Additionally, warning labels and recommendations for eye protection, if applicable, should be prominently displayed on the machine near the operator's area.
Verification: By checking the relevant drawings and inspection of the machine
NOTE For the laser characteristics, the information from the manufacturer of the laser can be useful.
Static electricity
If the machine is fitted with flexible hoses for chip and dust extraction, the hoses shall be able to lead charge to earth potential
Verification: By checking the relevant drawings and inspection of the machine.
Errors of Fitting
It shall not be possible to fit a saw-blade of greater diameter than the largest saw-blade for which the machine is designed
Verification: By checking the relevant drawings and inspection of the machine.
Maintenance
c) mass and stability (potential energy of elements which may move under the effect of gravity)
5.3.1 d) mass and velocity (kinetic energy of elements in controlled or uncontrolled motion);
- accumulation of energy inside the machinery: g) liquids and gases under pressure; 6.2.10, 6.3.5.4 5.4.6, 5.4.7
1.5 Drawing-in or trapping hazard 5.3.7
1.9 High pressure fluid injection or ejection hazard
2.1 Contact of persons with live parts (direct contact)
2.2 Contact of persons with parts which have become live under faulty conditions
4 Hazards generated by noise, resulting in:
4.1 Hearing loss (deafness), other physiological disorders (loss of balance, loss of awareness)
4.2 Interference with speech communication, acoustic signals
7 Hazards generated by materials and substances (and their constituent elements) processed or used by the machinery
7.1 Hazards from contact with or inhalation of harmful fluids and dusts
8 Hazards generated by neglecting ergonomic principles in machinery design related to:
8.1 Unhealthy postures or excessive effort 6.2.7, 6.2.8, 6.2.11.12,
8.2 Hand-arm or foot-leg anatomy 6.2.8.3 5.2.2, 5.4.5, 6.3
8.7 Design, location or identification of manual controls
8.8 Design or location of visual display units 6.2.8.8, 6.4.2 5.2.2
10 Unexpected start up, unexpected overrun/overspeed (or any similar malfunction) from:
10.1 Failure/disorder of the control system 6.2.11, 6.3.5.4 5.2.7, 5.2.8,
10.2 Restoration of energy supply after an interruption
10.3 External influences on electrical equipment
10.6 Errors made by the operator (due to mismatch of machinery with human characteristics and abilities, see 8.6)
11 Impossibility of stopping the machine in the best possible conditions
13 Failure of the power supply 6.2.11.1, 6.2.11.4 5.2.7, 5.2.8,
14 Failure of the control circuit 6.2.11, 6.3.5.4 5.2.1
17 Falling or ejected objects or fluids 6.2.3, 6.2.10 5.2.3, 5.2.6,
18 Loss of stability / overturning of machinery
5 Safety requirements and/or measures
The machine shall comply with the safety requirements and/or protective measures of this clause
The machine will be designed in accordance with EN ISO 12100:2010, specifically addressing hazards that are relevant but not significant, such as sharp edges, which are not covered in this document.
For guidance in connection with risk reduction by design, see EN ISO 12100:2010, 6.2, and for safeguarding measures, see EN ISO 12100:2010, 6.3
5.2.1 Safety and reliability of control systems
A safety-related control system encompasses all components from the initial manual control or position detector to the final actuator, such as a motor The safety-related parts of this control system must meet the specified performance level (PL) requirements outlined in EN ISO 13849-1:2008, addressing essential safety functions.
— starting and restarting: PL = c (see 5.2.3);
— moveable interlocked guards: PL = c (see 5.2.3, 5.3.7);
— moveable interlocked guards with guard locking: PL = c (see 5.2.3 and 5.3.7);
— interlocking of the cutting stroke with saw-blade rotation and work-piece clamping: PL = c (see 5.2.3);
— the initiation of the braking system: PL = b (see 5.2.4, 5.2.5 and 5.3.4);
— the two-hand control device: PL = c (see 5.2.3 and 5.3.7);
— on semi-automatic machines interlocking of self closing power operated guards with the position of the saw unit: PL = c (see 5.3.7.1);
— the active opto-electronic protective devices (light barriers): PL = c (see 5.3.7.4);
— the pressure sensitive mats: PL = c (see 5.3.7.4);
— the mechanically actuated trip devices (trip bar): PL = c (see 5.3.7.4);
— the work-piece clamping: PL = c (see 5.3.8)
Time delay devices shall be PL = c in accordance with the requirements of EN ISO 13849-1:2008
Verification: By checking the relevant drawings and/or circuit diagrams and inspection of the machine
NOTE For components characteristics the information from the component supplier can be useful
The primary electrical controls for initiating the saw-blade spindle drive motor and for standard stopping must be conveniently located on the machine, either beneath the work-piece support or on a control panel that is strategically positioned.
1) behind and above the fence; and
2) within 850 mm measured horizontally from the front edge of the work-piece support; and
3) at a maximum height of 1 600 mm from the floor level
The two-hand control device for managing the cutting stroke must be positioned at the front of the machine, within 1.0 m of the cutting line when aligned at 90° to the fence Additionally, it should be located below the workpiece support and have a minimum height of 750 mm above the floor level.
Where the control for the clamps is separate from the two-hand control device it shall be within 400 mm measured horizontally to the two hand control device
For the positioning of the emergency stops see 5.2.5
Verification: By checking the relevant drawings, measurement and inspection of the machine
Before operating or reactivating the machine, it is essential to ensure that all safety measures are in place and operational This is accomplished through the interlocking systems outlined in section 5.3.7 The machine can only be started or restarted by using the designated start control device.
The initiation of the cutting stroke shall only be possible after saw-blade rotation and work-piece clamping have been initiated
The saw unit cutting stroke shall be controlled by a two-hand control device of at least type III B in accordance with the requirements of EN 574:1996+A1:2008
All reset controls shall be located outside protected areas and not reachable when standing inside a protected area
For electrically started machines see EN 60204-1:2006, 9.2.5.2 The exceptions described in
The safety related part of the control systems (also see 5.2.1) for starting and the interlocking arrangements shall be at least PL = c in accordance with the requirements of EN ISO 13849-1:2008
Verification: By checking the relevant drawings and/or circuit diagrams, measurement, inspection and relevant functional testing of the machine
The machine shall be fitted with a stop control system, which when actuated shall disconnect power from all machine actuators unless STO is used and actuate the brake (if provided)
For normal stopping of PDS(SR) (power drive system, safety related) see EN 61800-5-2:2007, 4.2.2.2 “safe torque off (STO)” and 4.2.2.3 “safe stop 1 (SS1)”
The stop control must comply with category 1 as per EN 60204-1:2006, 9.2.2 Upon activation, the stopping sequence will first initiate the return stroke of the saw unit, followed by the removal of power to the work-piece clamping Next, power will be cut to the saw spindle drive motor, and the brake will be initiated if installed Finally, once the braking sequence is complete, power to the brake will be cut if an electrical brake is in place.
The stopping sequence must be fulfilled at the control systems level When utilizing a time delay device, it is essential that the time delay is no less than the maximum run-down time Additionally, the time delay should either be fixed or the adjustment mechanism must be sealed.
The safety related part of the control systems (also see 5.2.1) for normal stopping shall be at least PL = c in accordance with the requirements of EN ISO 13849-1:2008
Verification: By checking the relevant drawings and/or circuit diagrams, inspection and relevant functional testing of the machine
The requirements of EN ISO 13850:2008 apply and in addition:
The machine shall be fitted with an emergency stop control system which shall conform to the requirements of
EN 60204-1:2006, 9.2.5.4 and 10.7 However, the requirements of EN 60204-1:2006 do not apply The emergency stop control device shall be at any time of self latching type
For emergency stop of PDS(SR), see EN 61800-5-2:2007, 4.2.2.2 “safe torque off (STO)” and 4.2.2.3 “safe stop 1 (SS1)”
Emergency stops must be strategically placed based on machine size: within 1.0 m of both the loading and unloading positions, at the main control panel, within 500 mm of any two-hand control device (if applicable), and within 3.0 m of the saw unit.
A single emergency stop can be positioned to fulfil more than one of these requirements
When actuated the emergency stop shall disconnect power from all machine actuators and actuate the brake (if provided)
The emergency stop control must comply with category 1 as per EN 60204-1:2006, 9.2.2 Upon activation, the stopping sequence should first initiate the return stroke of the saw unit, followed by cutting power to the saw spindle drive motor and engaging the brake if available Once the braking sequence is completed, power to the brake should be cut if an electrical brake is installed.
The stopping sequence must be fulfilled within the control systems When utilizing a time delay device, it is essential that the time delay is no less than the maximum run-down time Additionally, the time delay can either be fixed or the adjustment mechanism should be sealed.
The safety related part of the control systems (also see 5.2.1) for the emergency stop shall be at least PL = c in accordance with the requirements of EN ISO 13849-1:2008
Verification: By checking relevant drawings and/or circuit diagrams, measurement, inspection and relevant functional testing of the machine
The integrated feed of the work-piece positioning mechanism shall only operate when the saw unit is in its rest position
For the integrated feed of the saw unit, see 5.2.3
Verification: By checking relevant drawings and/or circuit diagrams, inspection and relevant functional testing of the machine
5.2.7 Failure of the power supply
According to EN 60204-1:2006, sections 7.5, paragraphs 1 and 3, electrically driven machines must be designed to prevent automatic restart following a supply interruption once the voltage is restored.
In case of a loss of pneumatic or hydraulic pressure, it is essential to maintain the clamping of the workpiece until the saw-blade begins its return stroke Non-return valves, if utilized to ensure this safety measure, must be installed on the actuating cylinders.
The automatic restart of the machine shall be prevented after restoration of the pneumatic or hydraulic energy
Verification: By checking the relevant drawings and/or circuit diagrams, inspection and relevant functional testing of the machine
5.2.8 Failure of the control circuits
The requirements of EN 1037:1995+A1:2008 apply and in addition:
Control circuits must be designed to ensure that any circuit interruption, such as a broken wire or ruptured pipe, does not compromise safety functions, preventing issues like unintended machine starts or loss of workpiece clamping, in accordance with standards EN 60204-1:2006, EN ISO 4413:2010, and EN ISO 4414:2010.
Verification: By checking the relevant drawings and/or circuit diagrams, inspection and relevant functional testing on the machine
It shall be possible to fix stationary machines to a suitable stable structure, e.g floor Facilities for fixing are, e.g fixing holes in the machine frame (also see 6.3)
Verification: By checking relevant drawings, inspection and relevant functional testing of the machine
5.3.2 Risk of break up during operation
Guards for the saw-blade must be constructed from either steel with a minimum ultimate tensile strength of 350 N/mm² and a wall thickness of at least 1.5 mm, or from a light alloy that meets the specifications outlined in Table 2.
Table 2 — Light alloy saw-blade guard thickness and tensile strength
Polycarbonate should have a minimum wall thickness of 3 mm, or alternatively, other plastic materials that meet the criteria outlined in Annex B Additionally, cast iron must possess an ultimate tensile strength of at least 200 N/mm² and a wall thickness of no less than 5 mm.