BCX Series Operating Manual Page 109
D. CALIBRATION
Annual calibration will assure that the BCX cabinet is operating properly. Third party
services are available to perform this procedure.
1. Temperature Controls
It is suggested that a certified RTD simulator/reader be used to verify the PLC.
To calibrate the controller simply connect the simulator to each channel of the
controller (one at a time) and send 3 signals to the controller, 20ºC, 35ºC and 70ºC. If
the display screen reads the same as the simulator then everything is fine. If not,
contact Atlas Tech Service or an Atlas authorized representative. If the readings are
incorrect but linear, then an offset can be used to compensate. If the readings are non-
linear, then a component will need to be replaced.
2. RTD Temperature Calibration Procedure
a) Shut down the cabinet as described in the operation manual and relieve any
pressure from the Bubble Tower.
b) Prior to removing the RTDs, mark the wires so they can be put back correctly
when calibration is complete.
c) The RTDs will unplug and screw out of the plastic fittings. When replacing the
RTDs, use a thin layer of Teflon tape on the threads.
d) Heat a 1000 ml beaker of water (tap water is acceptable) to a temperature of
approximately 35ºC. This is close to the operating temperature of the RTDs.
e) Stir the water using a magnetic stirrer, and hang or hold the standard
thermometer along with the Thermocouple near the center of the moving water.
f) Compare the reading of the RTDs with the thermometer. If the temperature
shown on the controller is more than 1ºC different than the certified
thermometer, the RTDs should be replaced.
The RTDs can also be checked using the RTD simulator/reader.
Pressure gauges are calibrated at the factory prior to shipment. They may be
returned to ATLAS on an annual basis for re-calibration with certificate.
For some items, replacement cost is comparable to the cost of recalibration when
shipping and handling are taken into consideration. Contact ATLAS Tech Service
or an authorized Atlas representative before returning items for calibration.
