SOR Thermal Differential Flow Switch - Manual (Page 11)

Form 1024 (08.13) ©SOR Inc. 11/12
Cleaning
The probe may be cleaned by soaking, spraying solvents or detergent and water onto
the sensor tubes, or by ultrasonic cleaning.
Lime deposits can be safely removed by soaking in 20% hydrochloric acid. Warming
to 150°F is permissible to speed this process.
For unusual cleaning problems, contact the SOR factory to determine the exact materials
of construction and chemical compatibility before using strong acids or unusual
cleansers. Do not sandblast or scour the sensing probes with abrasive cleaners.
The sensing probes could be damaged by abrasives.
Troubleshooting
General Information
 Each unit is different. Settings may not be identical from unit to unit
 Moving the trip adjust pot closer to 100 produces
- Slower “On” response
- Faster “Off” response
 Set span at maximum possible flow rate (as far above the span setting as possible)
 Once again, the catalog J1 jumper settings are a starting point only
What do I do if...
... my zero or span is shifi ting during calibration?
The probes have likely not warmed up sufficiently. Apply power, place the probes in
the zero state process, and wait for 5 minutes. (In dry air, the heated probe may be
too hot to touch.)
... my setpoint has shifted shortly after calibration?
The probes were likely not allowed to warm sufficiently during calibration. Apply
power, place the probes in the zero state process, wait for 5 minutes, and repeat the
calibration process. In dry air, the heated probe should be hot to the touch.
... I cannot get the red light to illuminate when turning the zero pot?
• Make certain the heated probe is heating properly.
• Make certain the Trip Adjust pot is in the fully counter-clockwise position
• Change J1 jumper position and try again
• If calibrating for liquid flow, try performing the zero function in dry air
• Reverse Hot and Cold sensor wires and retry
... wire is the proper length for terminal assembly?
• Reverse the wires: 1 and 3
... I cannot get the green light to illuminate when turning the span pot?
• Make certain the heated probe is heating properly.
• Make certain the Trip Adjust pot is in the fully counter-clockwise position
• Change J1 jumper position and try again
• If calibrating for liquid flow, try performing the zero function in dry air
• Reverse Hot and Cold sensor wires and retry