Ashcroft B700 Pressure Switches - Manual

Installation and Maintenance Instructions for
ASHCROFT ® High Pressure B400 & B700
Snap Action Switches with Buna N, Viton and
Teflon Diaphragms 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.
INSTALLATION
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.
B400 Series standard – one
3 ⁄
4
˝ NPT conduit hole right side.
B700 Series standard – two
3 ⁄
4
˝ N PT conduit holes with one
permanent plug. NEMA 7 & 9 enclosures require proper conduit
seals and breathers as per the National Electrical Code.
B400 & B700 Series – XJL variation – two
3 ⁄
4
˝ NPT conduit
holes with two 3 ⁄
4
˝ to 1 ⁄
2
˝ NPT reducing bushings.
B400 Series – XJK variation – two
3 ⁄
4
˝ NPT conduit holes.
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.
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
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)
STANDARD RANGES
1000, 3000 psi
© 2014 Ashcroft Inc., 250 East Main Street, Stratford, CT 06614-5145, USA, Tel: 203-378-8281, Fax: 203-385-0499, www.ashcroft.com
All sales subject to standard terms and conditions of sale. I&M009-10210-Hi Prsr 3/14
TERMINAL BLOCK
SWITCH A
TERMINAL BLOCK
SWITCH B
2
1
3
2
1
3
NC
NO
C
NC
NO
C