MKS 250E - How to Perform the Controller Alignment Procedure

Maintenance Cha
p
ter Five: Maintenance and Troubleshootin
g
40
How To Perform the Controller Alignment Procedure
The following alignment procedure should be followed to verify the zero and full scale alignment
of the 250 controller. Allow the controller to warm up for at least 30 minutes. Note that the
main P.C. board has a block of test pins TP-1, 2, 3, etc. located behind the connector for the rear
panel board.
Equipment Needed
•
0 to 10 volt source for input
•
100 ohm, 1 Watt resistor for load
•
4 and 1/2 place, 0 to 10 volt meter
Connections
1. Connect the input source to the INPUT connector Pins 1 and 8 (Pin 8 should also be
connected to Pin 12).
2. Connect the 100 ohm resistor to the VALVE connector Pins C and D.
3. Verify that the controls are in the following positions:
SETPOINT POT CCW (000)
SETPOINT INT/EXT INT
RANGE 10V
PHASE LEAD CCW
GAIN CW
MODE CLOSE
NORmal/REVerse NORMAL
115/230 (Rear Panel) As available
4. Verify that the A.C. supply is either 115 +15 or 230 +
15 volts A.C.
5. Check the voltage at the test points listed in Table 10, page 41, and readjust the
appropriate control if necessary.
Note
Ref (GND) at the test DVM should be the A GND test point next to C18.