Mitsubishi Electric CITY MULTI, Техническое и сервисное руководство

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117
OCH673D
<HIGH PRESSURE SENSOR>
• Comparing the High Pressure Sensor Measurement and Gauge Pressure
By configuring the digital display setting switch (SW1) as shown in the figure below, the pressure as measured by the high
pressure sensor appears on the LED1 on the control board.
(1) While the outdoor unit is stopped, compare the gauge pressure and the pressure displayed on self-diagnosis
LED1, 2.
1) When the gauge pressure is between 0 and 0.098 MPaG [14 PSIG], internal pressure is caused due to gas leak.
2) When the pressure displayed on self-diagnosis LED1, 2 is between 0.098 MPaG [14 PSIG], the connector may be defec -
tive or be disconnected. Check the connector and go to (4).
3) When the pressure displayed on self-diagnosis LED1, 2 exceeds 5.0 MPaG [725 PSIG], go to (3).
4) If other than 1), 2) or 3), compare the pressures while the sensor is running. Go to (2).
(2) Compare the gauge pressure and the pressure displayed on self-diagnosis LED1,2 after 15 minutes have passed
since the start of operation. (Compare them by MPaG [PSIG] unit.)
1) When the difference between both pressures is within 0.25 MPaG [36 PSIG], both the high pressure sensor and the con -
trol board are normal.
2) When the difference between both pressures exceeds 0.25 MPaG [36 PSIG], the high pressure sensor has a problem.
(performance deterioration)
3) When the pressure displayed on self-diagnosis LED1, 2 does not change, the high pressure sensor has a problem.
(3) Remove the high pressure sensor from the control board to check the pressure on the self-diagnosis LED1, 2.
1) When the pressure displayed on self-diagnosis LED1, 2 is between 0 and 0.098 MPaG [14 PSIG], the high pressure sen -
sor has a problem.
2) When the pressure displayed on self-diagnosis LED1, 2 is approximately 5.0 MPaG [725 PSIG], the control board has a
problem.
(4) Remove the high pressure sensor from the control board, and short-circuit between the pin 2 and pin 3 connectors
(63HS) to check the pressure with self-diagnosis LED1, 2.
1) When the pressure displayed on the self-diagnosis LED1, 2 exceeds 5.0 MPaG [725 PSIG], the high pressure sensor has
a problem.
2) If other than 1), the control board has a problem.
• High Pressure Sensor Configuration (63HS)
The high pressure sensor consists of the circuit shown in the figure below. If 5 V DC is applied between the red and the
black wires, voltage corresponding to the pressure between the white and the black wires will be output, and the value of this
voltage will be converted by the microprocessor. The output voltage is 0.078 V per 0.098 MPaG [14 PSIG].
Note: The pressure sensor on the body side is designed to connect to the connector. The connector pin number on the body
side is different from that on the control board side.
Body side Control board side
Vcc Pin 1 Pin 3
Vout Pin 2 Pin 2
GND Pin 3 Pin 1
ON
1 2 3 4 5 6 7 8
The figure at left shows that the switches 1 through 4 are set to ON and 5 through 8 are set to OFF.
SW1
ON
1 2 3 4 5 6 7 8
3
2
1
RD
WH
BK
SENSOR
5 V DC
GND
63HS
Vout
MICRO
PROCESSOR
OUTDOOR MULTI CONTROLLER
CIRCUIT BOARD
3
–
1
: 5 V (DC)
2
–
1
: Output Vout (DC)
Pressure: 0–5.0 MPaG [725 PSIG]
Vout: 0.5–4.5 V
0.078 V/0.098 MPaG [14 PSIG]
0.5
2.5 5
2.5
4.5
Vout (V)
PRESSURE
(MPaG)
(PSIG) 363 725
0