Despatch RFD1-42-2E with Protocol Plus - Manual (Page 61)

53
Tests
Tests should be performed carefully and regularly. The safety of personnel as well as
the condition of equipment may depend upon the proper operation of any one of the
functions of the temperature control. Test the control every 40 hours. Check that the
heater LED is cycling on and off, indicating that the heater is working. Also check the
high limit function to make sure it is working properly.
To test the high limit:
1.
Go to Manual Mode and enter control setpoint value at least 20ºF (11ºC) lower
than the current process temperature.
2.
Press the Menu key and lower the high limit setpoint to a value just below the
current process temperature.
3.
The high limit alarm indicator should flash and a high limit alarm message should
be displayed. Verify that the heater relay has been disabled by checking that
2LED on the control panel circuit board is not lit.
4.
Return the control setpoint and high limit setpoint values to their original values.
5.
Press the Reset key.
The airflow switch and purge timer should also be tested every 40 hours.
To test the airflow switch and purge timer:
1.
Allow the oven to stabilize at its minimum operating temperature by turning the
heater off. Place all dampers in the closed position.
2.
Cycle power to the system.
3.
The airflow switch should be closed but the heater relay should remain de-
energized until the purge timer times out. This can be verified by monitoring the
purge timer.
Indicators 1LED and 2LED should be lit. 3LED should remain off until the purge timer
times out.