SOR RT Nuclear Qualified Temperature Switch - Manual (Page 2)

2/4 Form 1473 (05.13) ©SOR Inc.
RT Housing
NOTE: For switches that monitor HELB (High Energy Line Break), use “Recommended Tempera-
ture Measurement Procedure for Switches Used to Sense Temperature of Liquids and Steam” for
the most accurate results.
Direct Mount
1/8 NPT(F)
Vent Connection
Cover Screws
Body
Process Connection
Sensing Bulb
3/4 NPT(F)
Conduit Connection
Mounting Holes
Recommended temperature measurement procedures for switches used to sense
temperatures of liquids and steam with set points above 200°F:
Recommended procedures for set points above 200°F are identical to those for set
points below 200°F with the exception of the bath used to test the switches. We
recommend either a circulated oil bath or a fluidized sand bath. The bath should be
tested for uniformity of temperature from top to bottom and side to side. If necessary,
steps may be taken to improve the uniformity of temperature, such as altering the air
flow through a sand bath or improving circulation or stirring.
Recommended temperature measurement procedures for switches used to sense air
or gas temperature:
Switches used to measure the temperature of air or gas should be tested in such a way that
it simulates the actual service conditions as closely as possible. Chances of measurement
error are much greater in air because of its poor thermal conductivity. Rate of change of
temperature, velocity of air flow, location of sensing bulb, and location of standard must
be duplicated as closely as possible for successive calibration checks to assure repeatable
results. If the switch is being used as a room thermostat, the entire switch should be
placed in a test oven for calibration and testing. If only the sensing bulb is exposed to the
air or gas being measured, then only the sensing bulb should be inserted into the oven or
test apparatus for calibration and testing. In this case the switch housing should be kept at
room temperature.