Curtis PMC 1209B/1221B/1221C/1231C Manual
25
MAINTENANCE & ADJUSTMENT
Fig. 17
Adjustment pots.
Use the following adjustment procedure.
The keyswitch should be off during
adjustment.
1. Remove the socket head screw (1/8" Allen) for the adjustment you
want to make.
2. Adjust the internal potentiometer using a small
insulated
screwdriver
(available from Curtis).
3. Replace the socket head screw and nylon seal washer. To prevent
stripping, do not over-tighten.
POTBOX
Maintenance
Potbox maintenance is similar to controller maintenance: inspect for integrity of
connections and mounting, and clean (with a moist rag) as required.
Adjustment
Curtis PMC potboxes are factory set and rarely require user attention. To test and
adjust, connect an ohmmeter to the potbox wires and use this procedure:
1. With the spring holding the lever arm against the return stop, the
resistance should be less than 50 ohms. Slowly move the lever. If the
resistance abruptly starts to increase when the lever is 3 mm (1/8") from
the stop (1.5 mm [1/16"] for potboxes without the microswitch), no
adjustment is needed.
PLUG CURRENT ADJUST
(CW = higher plug current)
ACCELERATION RATE ADJUST
(CW = faster acceleration)
CURRENT LIMIT ADJUST
(CCW = lower current limit)
