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PCB and Functions

2. Indoor Unit Control PCB

1. Indoor Unit Control PCB Switches and Functions Indoor unit control PCB

T10:

6P plug (yellow): Used for remote control. (Refer to the remote control section.)

(CN61)

Control items: (1) Start/stop input

(2) Remote controller prohibit input

 

(3) Start signal output

(4) Alarm signal output

EXCT:

2P plug (red): Can be used for demand control. When input is present, forces the unit to operate with the thermostat

(CN73)

OFF.

 

DISP:

2P plug (white): Short-circuiting this plug allows the unit to be operated by the remote controller, even if it is not

(CN72)

connected to an outdoor unit.

 

 

(In this case, alarm "E04," which indicates trouble in the serial communication between the indoor and outdoor unit,

 

does not occur.)

 

CHK:

2P plug (white): Test pin. Short-circuiting this pin allows the indoor FM (H fan speed), drain pump, fl ap motor (F1

 

position), and electronic expansion valve full-open position to be checked.

 

However this function turns OFF if the indoor unit protection mechanism is activated. The unit can be operated even

 

if the remote controller and outdoor unit are not connected. However even if the remote controller cannot is con-

 

nected, it cannot be used to operate the unit. This function can be used for short-term tests.

JP1:

Jumper wire: Allows selection of the T10 terminal start/stop signal. (Refer to the remote control section.) Status at

(J01)

shipment: Pulse signal

 

 

Jumper wire cut: Static signal (continuous signal)

FAN DRIVE 2P plug (white): This terminal sends a signal to the ventilation fan when the FAN button on the wired remote con- troller is used to operate a commercially-available ventilation fan. (Refer to the remote control section.)

Use a ventilation fan which can accept no-voltage A contact as the external input signal.

FILTER:

2P (white): This terminal is used to connect contact input from the differential pressure switch which detects fi lter

(CN70)

clogging. When the contacts turn ON, "FILTER" is displayed on the wired remote controller.

Power LED: LED (red): Illuminates when power is supplied. Blinks when there is a failure in the EEPROM (IC10: nonvolatile memory).

EEPROM: Nonvolatile memory: Memory which stores the unit type data and other information. When the PCB is replaced,

(IC10) remove the EEPROM from the old PCB and install it onto the new PCB. If an IC failure occurs, replace with a new IC which was provided with the service PCB, and set the necessary information from the wired remote controller. (For the procedure, refer to the servicing technical materials.)

GRL:

For AC fan motor (CR-UXRP71B-B: 3P (yellow))

(CN20)

For DC fan motor (CR-SXRP56B-B: 5P (blue))

zThe indoor unit power terminal plate will be a 7P type or may be a 5P type. (Refer to the fi gure at below.) The basic wiring dia- gram shows the 7P-type terminal plate. Therefore the terminal plate may differ from the illustrations.

7P-type terminal plate

5P-type terminal plate

R S

T U1 U2

1 2

L1 L2

U1 U2

Power

Inter-unit

Remote

Power

Remote

supply

control line

control line

supply

control line

4-6

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Image 92
Sanyo UHX1852, UHX2452, UHX0752, UHX1252, UHX3652, THX2452, THX1252, THX1852, XHX1852, XHX3652 Indoor Unit Control PCB, T10, JP1