Movincool Office Pro 10, Service Manual

Page: 22 / 56

ELECTRICAL SYSTEM
14
RELAY BOARD FUSE
RELAY BOARD
EVAPORATOR FAN
MOTOR CAPACITORS
MAIN WIRE HARNESS
(WIRE ASSEMBLY
TERMINAL BLOCK
DIP SWITCH
CONDENSER FAN
MOTOR CAPACITOR
COMPRESSOR
CAPACITOR
Control Box
1. Basic Operation of Office Pro 10 Electrical Circuit
There are two basic components used to control the operation of the Office Pro 10 Electrical System:
• Control Panel Assembly
• Control Box
The Control Panel Assembly contains the Control Panel, Control Board (with inputs for the freeze and
room temperature thermistors), drain switch, and a microprocessor.
A. Fan “Only” Mode (Evaporator)
Low Fan Mode - When the “Low” Fan Mode button on the control panel is pressed, the microprocessor
turns on the button’s LED and activates the Fan “On” Relay (Relay Board), sending line voltage
(115 VAC) to the N.C. (Normally Closed) contacts of the fan “mode” relay. This output is connected to
the J5 terminal (relay board) where the LOW SPEED wire of the fan motor is connected.
Note: Low fan mode does not operate in Fan “Only” mode.
High Fan Mode – When the “High” Fan Mode button on the control panel is pressed, the microproces-
sor turns on the button’s LED and activates both the Fan “On” Relay and Fan “Mode” Relay. This sends
line voltage (115 VAC) from the Fan “On” Relay to the N.O. (Normally Open) contacts of the Fan “Mode”
Relay. This output is connected to the J6 terminal (relay board) where the HIGH SPEED wire of the Fan
Motor is connected.
B. Cool Mode - In Addition to Fan “Only” Mode (as described above)
When the Cool On/Off button on the control panel is pressed, the microprocessor turns on the button’s
LED and if the Temperature Set Point is less than the current room temperature, this activates the
Compressor Relay (Relay Board) after a hundred and twenty (120) second delay. This sends line voltage
(115 VAC) to the J4 terminal (Relay Board) where the wire from the Compressor wire harness is con-
nected.
2. Control Box