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Installation and Maintenance Instructions for B400 & B700 ASHCROFT ® Snap Action Switches for Pressure Control INTRODUCTION The Ashcroft pressure switch is a precision built agency appr

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PRESSURE GAUGE INSTALLATION, OPERATION AND MAINTENANCE

PRESSURE SWITCHS PRESSURE GAUGE INSTALLATION, OPERATION AND MAINTENANCE

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Installation and Maintenance Instructions for

B400 & B700 ASHCROFT ® Snap Action

Switches for Pressure Control

INTRODUCTION

The Ashcroft pressure switch is a precision built agency

approved control device which features a mechanical snap

action switch Controllers are available for operation on pressure

or vacuum with fixed or variable differential Also manual reset

types for operation on increasing or decreasing pressure The

manual reset types remain tripped until reset by pressing a

but-ton on top of the enclosure Standard electrical switch is SPDT,

available with various electrical characteristics Two SPDT switch elements mounted together are available except on variable Deadband and manual reset types Various wetted material con-structions for compatibility with a range of pressure media may

be obtained.

The Ashcroft snap action pressure switch is furnished in the standard NEMA 4 and explosion-proof NEMA 7 & 9 enclosure styles Both enclosures are epoxy coated aluminum castings.

4.03 (102)

Ø 0.28 X 3 HOLES (7) 0.22

(6)

3.32

(83) 5.95

(151)

1.25

(32)

0.50

(13)

0.14

2.78 (71) 3.50 (89)

Ø 5.12 (130)

Ø 0.34

2 HOLES 0.36 (9)

0.25 (6)

2.27 (58) 1.25 (32)

2.77 (70)

5.62 (143)

3.06 (78)

2.84 3/4 NPT

1/4 NPT FEMALE

BRACKET WHEN REQURIED “XBP”

VARIATION

(72)

3.32 (84)

0.22 (6)

Ø 0.28 X 3 HOLES (7)

3.26 (83)

5.68 (144)

4.03 (102)

2.77 (70)

2.27 (58)

0.25 (6)

5.11 (130) 2.50 (64)

1.25 (32)

Ø 2.31 (59) 3/4 NPT B400

B700

5.20 (132)

3.62

(92)

2.18 (55) 0.32 (8)

4.37

(111)

1.37

(35)

Ø 0.28 x 3 HOLES

(7)

1.11

(28)

Ø 5.12 (130)

1.93 (49)

2.78 (71) 3.50 (89)

0.36 (9) 1.39 (35)

6.43

163

0.50

(13)

0.36

(9)

Ø 0.34 X 2 HOLES (9)

Ø 3.90 (99)

0.03 (1)

3.58 (91)

0.31 (8)

5.62 (143) 3.06 (78) 1.22 (31)

1/4 NPT FEMALE

3/4 NPT

2 HOLES

BRACKET WHEN REQUIRED "XBP"

VARIATION

1.93 (49)

5.20 (132)

3.62 (92)

2.18 (55)

0.32 (8)

4.37 (111)

1.37 (35)

5.73 (146)

Ø 0.28 x 3 HOLES (7)

Ø 3.90 (99)

0.03 (1)

3.58 (91)

2.31 (59)

0.31 (8)

1.22 (31)

1/4 NPT FEMALE 3/4 NPT 2 HOLES

1.8 lb (.81 kg)

2.7 lb (1.2 kg)

2.7 lb (1.2 kg) 3.6 lb

(1.6 kg)

STANDARD RANGES

15, 30, 60, 100, 200, 400, 600 psi

1000, 3000 psi 30˝Hg vac.-0

STANDARD RANGES

10, 30, 60, 100, 150 ˝H2O

15˝H2O vac.-15˝H2O

© 2007 Ashcroft Inc., 250 East Main Street, Stratford, CT 06614-5145, USA, Tel: 203-378-8281, Fax: 203-385-0499, www.ashcroft.com

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These controls are precision instruments and should never be

left with internal components exposed During installation insure

that covers are in place and conduit openings are closed except

when actually working on the control.

MOUNTING B400 AND B700 SERIES

Three holes external to the enclosure for surface mounting.

Location of these holes is shown on the general dimension

drawing They may also be mounted directly on pressure line

using the pressure connection When tightening control to

pres-sure line, always use the wrench flats or hex on the lower housing.

ELECTRICAL CONNECTIONS

Remove cover

B400 Series – two screws hold cover to enclosure

B700 Series – cover unscrews

CONDUIT CONNECTIONS

Note – It is recommended that Teflon tape or other sealant be

used on conduit, bushing or plug threads to ensure integrity of

the enclosure.

permanent plug NEMA 7 & 9 enclosures require proper conduit

seals and breathers as per the National Electrical Code.

B400 SERIES

SPDT – Wire directly to the switch according to circuit

require-ments On controls with pilot lights wire lights according to circuit

diagram on inside of cover See special wiring instruction tag for

single switches with two pilot lights and dual switches with one

or more lights.

2 SPDT – Dual switching elements consist of two SPDT switches

mounted together in a bracket Switches are calibrated to have

simultaneous operation within 1% of range either on increasing

or decreasing pressure but not in both directions Wire directly to

the front and rear switch according to circuit requirements.

Leads are provided on rear switch color coded as follows:

Normally Closed – Red

See SPDT instructions for pilot light hook-up.

When hermetically sealed switch elements(s) are supplied, the lead color coding is as follows:

Normally Closed – Red

B700 SERIES SPDT – Wire directly to the switch according to circuit requirements.

2 SPDT – Wire to front switch terminal block (left) and rear

insert in proper terminal connector and tighten clamping screw

to secure.

ADJUSTMENT OF SETPOINT

located centrally at the bottom on the inside of the enclosure For accurate setpoint calibration, mount the switch on a cali-bration stand, a pump or catalog No.1305 deadweight gauge tester A suitable reference standard such as an Ashcroft Duragauge or Test Gauge is necessary to observe convenient changes in pressure.

As received, the pressure switch will normally be set to approximately 90% of the indicated range Pressurize the system to required setpoint and turn the adjustment nut until switch changes mode Direction of turning is indicated on a label affixed to the inside of the control enclosure When setpoint has been achieved raise and lower pressure to insure that setpoint

is correct.

After installation of the control replace cover to insure electri-cal safety and to protect internal parts from the environment.

B450 and B750 VARIABLE DEADBAND SWITCHES

Deadband is varied by rotating the wheel on the precision switch When viewed from the front of the enclosure, rotation to the left increases deadband – rotation to the right decreases deadband Letters on the wheel may be used as a reference Deadbands obtainable will vary from 0.5% to 9% of pressure range depending on range segment and type of diaphragm.

ADJUSTMENT OF SETPOINT

As received, the pressure switch will normally be set to approxi-mately 90% of range Rotate the wheel on the MICRO SWITCH all the way to the right; this will provide smallest deadband Pressurize the system to the required setpoint and turn the adjustment nut until the switch changes mode Lower the pressure to reset the switch Rotate the wheel on the MICRO SWITCH until the desired deadband is obtained The upper setpoint will be changing upward with this adjustment Lower the pressure to reset the switch Then increase the pressure to the desired setpoint and turn the adjusting nut until the switch changes mode Lower the pressure and check resetpoint and deadband.

Note – As indicated above, adjustment of setpoint is made by

and bracket adjusting screw are factory sealed and should not be tampered with.

Installation and Maintenance Instructions for

B400 & B700 ASHCROFT ® Snap Action

Switches for Pressure Control

TERMINAL BLOCK SWITCH A

TERMINAL BLOCK SWITCH B

2

1 3

2

1 3

NC NO C

NC

NO

C

Note – Since vacuum models are already above setpoint at

atmosphere, the Normally Open (NO) circuit will be closed as received.

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INSTALLATION REQUIREMENTS

• To minimize the risk of injury, the switch enclosure must be

selected according to the area classification and installed

according to the required safety and electrical codes.

• Before operating the switch all conduit entries and/or junction

boxes need to be closed according to the required safety and

electrical codes.

• To attain the degree of protection listed on the switch it may

be necessary to add required conduit fittings.

• The switch must be protected from moisture, shock and/or

extreme vibration.

• The ambient temperature limits for switches are –20 to 150°F,

(–28 to 65°C).

CAUTIONS

• Always install the cover after wiring the switch and before

power is supplied.

• Before removing the cover in hazardous areas be sure there

is no explosive atmosphere present and the power supply is

turned off.

• For ATEX approved switches all safety locking devices and

electrical earthing must be installed or connected before

operating.

• Never carry a temperature switch by holding only the stem,

bulb or capillary.

• Do not exceed ranges, current and/or voltage limits.

• The protection degree of the switch is only valid when the

switch is installed in accordance with all safety and electrical

codes and regulations.

CLEANING

• Never use aggressive solvents.

• Do not use high pressure water to clean the switch.

MAINTENANCE/TROUBLESHOOTING

• All Ashcroft switches require little or no maintenance.

• Be sure that the case is closed at all times.

• When the switch is exposed to process media that may

hard-en and/or build up in the pressure port, the switch should be

removed and cleaned as needed.

• If the switch does not function, only trained and skilled

per-sonnel should check on the wiring, power supply and/or

mounting.

• If the problem can not be solved, please contact one of the

Ashcroft affiliates or distributors.

ELECTRICAL CONNECTIONS

• Only trained and skilled personnel are allowed to install the

wires to the electrical terminals of the switch.

• Cable couplers, glands and conduit connectors must have the

correct electrical approvals.

• Always follow safety and electrical regulations when

connect-ing these devices.

• The system ground of the device is marked with a green

colored screw and/or by the ground symbol.

• ATEX approved switches have an external ground screw that

must be connected.

• Micro switch terminals and wire color codes:

© 2007 Ashcroft Inc., 250 East Main Street, Stratford, CT 06614-5145, USA, Tel: 203-378-8281, Fax: 203-385-0499, www.ashcroft.com

Installation and Maintenance

Instructions for CE Mark on ASHCROFT®

Switches/Low Voltage Directive 73/23/EEC

TABLE 1: MICRO SWITCH ELECTRICAL RATINGS

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électriques

é ocessus av

en apte v

1) V=

Druck-/Differenzdruck- und Tempera- turschalter 400er und 700er Serie

Pressure-/differential pressure- and temperature sw

Instruction de Service Pressostat, pressostat différentielle et thermostat série 400 et 700 Ashcroft Instruments GmbH Germany

England/Angleterre Unit 5 William James House Cowley Road, Cambridge CB4 0WX

France/Frankreich „206“ ZA Le Mandinet Rue des Campanules

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n e

English 1 Installation

2 Mounting -

B/D/T450 and B/D/T750 h

5 Caution -

6 Cleaning -

7 -

Français 1 -

2 Montage -

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eau du mano est supérieure à la température

-20 … 60 °C Les températures max

remplis d’un bain d’huile amortisseur Température du "process" max

pression doit être amenée à la pression Fermer l’ensemble des v

tie basse pression a des fuites Si le la coté basse pression et ouv

sinon les ergots de la lunette pourraient être endommagés Pour retirer la lunette, tapoter dans

Faire tourner le bouton „B“ pour ajuster le zéro Serrer la v

Ausführung ex

liquid filled à bain

- 18 65 - 45 65

Pressure- and DP gauge Instruction de Service Manomètre et Manomètre différentiel Ashcroft Instruments GmbH Germany

England/Angleterre Unit 5 William James House Cowley Road, Cambridge CB4 0WX

France/Frankreich „206“ ZA Le Mandinet Rue des Campanules

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Betracht kommenden Anforderungen

stellung übereinstimmen Ohne Angabe auf dem Zifferblatt ist die Gebrauchslage 90°

plosionsfähiger Atmosphäre (Modell T5500/T6500): -20 … 60 °C

Bei gasförmigen Stoffen kann sich die Temperatur durch Kompres- sionsw

- Ventile innerhalb des Anzeigebereiches Fällt der Zeiger, ist die Plusleitung un- dicht oder das Ausgleichsv

stehen 6 Nullpunktkorrektur -

(1) gegen den Uhrzeigersinn lösen Nach der Nullpunktkorrektur Schr

fester Ausführung eine 1/8 Umdrehung, bei hermetisch dichter und gefüllter Ausführung eine 1/3 Umdrehung nachziehen

Gehäuseseite - (siehe Bild 2)

Feststellschraube A lösen Mit der Justierschraube B den Nullpunkt einstellen Feststellschraube A in Justierschraube B eindrehen

2 Mounting -

feature (liquid filled or pulsation dampener) The measuring instrument must be protect against damages, great pollution,

one-sided heat radiation for the dp gauge Please note the freezing point of media and choose a frost-protected place for the dp gauges

3 Operation - mark

-20 … 60 °C The admissible temperature of the process media depends on the instrument construction as w

For gaseous media the temperature can rise as result of compres- sion Therefore the max

and the pressure has to be released to atmosphere The pointer tip must stay w

5 Maintenance - -

Rotated knob B until required adjustment Tighten screw

2 Montage -

Noter la point de gel du fluide et choisir une place protégée du gel pour les ma- no’s différentiels

...

liquid filled à bain

- 18 65 - 45 65

Pressure- and DP gauge Instruction de Service Manomètre et Manomètre différentiel Ashcroft... media the temperature can rise as result of compres- sion Therefore the max

and the pressure has to be released to atmosphere The pointer tip must stay w

5 Maintenance

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