SOR Opposed Piston - Manual (Page 2)

2/12 Form 279 (02.13) ©SOR Inc.
Installation
This type of differential pressure switch can be installed in any position.
WEATHERTIGHT HOUSING
Attach the device to a suitable surface or pipe stanchion bracket with two 1/4-inch diameter
bolts. Line mounting by either process or electrical connection is not recommended.
EXPLOSION PROOF HOUSING
Attach the device to a suitable surface or pipe stanchion bracket with two 1/4-inch diameter
bolts. The TA housing must be attached with 2-inch U-bolts over the housing hubs or
two 1/4 in. diameter bolts. Line mounting by either process or electrical connection is not
recommended.
NOTE: When mounting to an irregular or uneven surface, install rubber washers on the bolts
between the housing and the mounting surface to prevent housing deformation.
If a breather drain is installed, the device should be mounted with the
breather drain pointing downward (6 o’clock) so condensation will drain
from the housing.
Failure to mount the housing on a fl at mounting surface may result in
torsional forces on the housing that could cause false trips or render the
pressure switch inoperative.
There are only three wetted parts on the Hi and Lo process connections: pressure port,
diaphragm and o-ring. A metal diaphragm may be welded to the pressure port for certain
applications, thereby eliminating the o-ring.
This force-balance system virtually eliminates friction and resultant wear while yielding
excellent repeatability.
These differential pressure switches are well suited for a variety of process applications.
They are not intended for high pressure, fluid power (hydraulic) applications where high
shock pressures and high cycle rates are expected.
Safety Integrity Level (SIL) Installation Requirements
The SOR pressure switches have been evaluated as Type-A safety related hardware.
To meet the necessary installation requirements for the SIL system, the following
information must be utilized:
„ Proof Test Interval shall be one year.
„ Units may only be installed for use in Low Demand Mode.
„ Products have a HFT (Hardware Fault Tolerance) of 0, and were evaluated in a
1oo1 (one out of one) configuration. Form 1538 (03.12) ©2012 SOR Inc.