Mitsubishi Electric CITY MULTI CMB-P1016V-F, Руководство по обслуживанию

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TROUBLESHOOTING
[1] Principal Parts
Pressure Sensor
(1)
1) Check for failure by comparing the sensing pressure according to the high pressure/low pressure pressure sensor
and the pressure gauge pressure.
Set SW1 as shown below to display the high and low pressure sensor data displayed digitally by the light emitting
diode LD1.
High Pressure
(Units are kg/cm 2 G)
Low Pressure
1 In the stopped condition, compare the pressure readings from the gauge and from the LD1 display.
(a) If the gauge pressure is 0~1 kg/cm 2 G (0.0098MPa), the internal pressure is dropping due to gas leakage.
(b) If the pressure according to the LD1 display is 0~1 kg/cm
2
G (0.0098MPa), there is a faulty contact at the connec-
tor, or it is disconnected. Proceed to 4.
(c) If the pressure according to the LD1 display is 32 kg/cm 2 G (3.14MPa) for high pressure or higher, proceed to 3.
(d) If other than (a), (b) or (c), compare the pressure readings during operation. Proceed to 2.
2 Compare the pressure readings from the gauge and from the LD1 display while in the running condition.
(a) If the difference between the two pressures is within 1 kg/cm 2 G (0.098MPa), for high pressure and 0.03MPa
for low pressure both the affected pressure sensor and the main MAIN board are nor mal.
(b) If the difference between the two pressures exceeds 1 kg/cm
2
G (0.098MPa), for high pressure and 0.03MPa
for low pressure the affected pressure sensor is faulty (deteriorating performance).
(c) If the pressure reading in the LD1 display does not change, the affected pressure sensor is faulty.
3 Disconnect the pressure sensor from the MAIN board and check the pressure according to the LD1 display.
(a) If the pressure is 0~1 kg/cm
2
G (0.098MP for low pressure a) y, the affected pressure sensor is faulty.
(b) If the pressure is 32 kg/cm 2 G (3.14MPa) for high pressure or higher, the MAIN board is faulty.
If ambient temperature is below 30
°
C, main board is faulty.
If ambient temperature is above 30
°
C, proceed to 5.
4 Disconnect the pressure sensor from the MAIN board and shor
5 Disconnect the 63HS connector from the main board and replace it with the 63LS connector and check the LD1 display.
t out the No. 2 and No. 3 pins of the connector
(63HS, 63LS), then check the pressure by the LD1 display.
(a) If the pressure according to the LD1 displa
(a) If data is 1.37MPa or above then main board is faulty.
y is 32 kg/cm
2
G (3.14MPa) for high pressure and 1.37MPa for low
pressure , the affected pressure sensor is faulty.
(b) If other than (a), the MAIN board is f
(b) If (a) is not the problem then the 63LS sensor is faulty.
aulty.
2) Pressure sensor configuration.
The pressure sensors are configured in the circuit shown in the figure at right. If DC 5 V is applied between the red
and black wires, a voltage corresponding to the voltage between the white and black wires is output and this voltage
is picked up by the microcomputer. Output voltages are as shown below.
Output power voltage high pressure 0.1 V per (0.098MPa)
Output power voltage low pressure 0.3 V per (0.098MPa)
1 2 3 4 5 6 7 8 9 10
ON
1 2 3 4 5 6 7 8 9 10
ON
Connector
V
Pressure 0-2.94MPa
out 0.5~3.5 V
GND (Black)
Vout (White)
Vcc (DC5V) (Red)
63HS/
63LS
on the LD1 displa
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