The Moducontrol supplies 0 to 10 volts dc and 230 volts ac to the Penn P66AA-1C. The Speed Controller ramps up to 90 % of the normal fan speed for 7 seconds and then begins to modulate to the required speed. The Speed Controller provides power to the fan motor for as long as the cooling caller exists. As soon as the cooling caller is complete the Moducontrol stops the 0 to 10 vdc and line voltage shutting off the fan motors several seconds later.
Check the fan components and wiring as above. Check position of dipswitch # 7 on the Moducontrol. Switch # 7 must be On. The Moducontrol sends0 to 10 vdc fro m M6-3 and M6-4 to E3 and E4 of the speed controller. The speed controller must have 24 volts at terminals E1 and E2 from an independent transformer. Speed controller terminal L receives power from the Moducontrol terminal M1S-1. Terminals L and M of the speed controller close to provide power to the fan motors.