Daikin RXYQ-TA Series Service Manual page 161

SiUS341615E
[2-26]: Night-time low noise operation start time
2 (default)
This setting is used in conjunction with setting [2-22].
[2-27]: Night-time low noise operation stop time
3 (default)
This setting is used in conjunction with setting [2-22].
[2-28]: Power transistor check mode
To evaluate the output of the power transistors. Use this function in case error code is displayed related to
defective inverter PCB or inverter compressor is locked.
Default value: 0. Power transistor check mode is not active.
Field setting 1: Power transistor check mode is active.
Function:
Inverter PCB gives output of 10 Hz in sequence by all 6 transistors. Remove the U/V/W terminals of
the inverter compressor, and connect to the inverter checker module. If all 6 LEDs blink, the
transistors switch correctly.
When the power transistor check mode is interrupted, after internal power circuit is disconnected on
the inverter PCB, 2 LEDs will light up to indicate discharge of the DC voltage. Wait till the LEDs are
OFF before returning fasten terminals back to the compressor terminals.
Minimum requirements to refer to the result on the inverter checker module:
All 3 phases and neutral are available, and
Inverter PCB control is active. Check if the green LED "HAP" on the inverter PCBs are blinking
normal (approx. 1/ second). If LEDs are OFF, need to exit the "standby mode" of the inverter:
Diode module generates the required 500 VDC.
Cautions:
In case there is more than 1 compressor in a system (outdoor is 14 HP or larger, or multi outdoor
configuration) all compressor inverter PCBs will perform the power transistor check. In such case,
disconnect U/V/W fasten terminals on all compressors. Avoid accidental touch of fasten terminals
to short circuit or earth leak to casing.
To stop the power transistor check mode, change setting to default 2-28-0.
Output to U/V/W will also stop when outdoor unit main PCB decides standby mode of inverter
circuit.
Field Settings
Value Start time automatic night-time low noise
[2-26] operation (approximately)
1
3
Value Start time automatic night-time low noise
[2-27] operation (approximately)
1
2
Disconnect and reconnect power supply control PCB, or
Forced thermostat ON condition, or
Make shortly set 2-6-1 (forced thermostat ON indoor), or 2-20-1 (manual refrigerant charge).
Once the LED is blinking on the inverter PCB, change related setting immediately back to
set 0 to deactivate related function.
20:00
22:00
24:00
6:00
7:00
8:00
Field Settings for Outdoor Unit
148