L1/L4 Troubleshooting; L2 Troubleshooting - Midea VRF V4 Plus I Series Manual

MCAC-VTSM-2014-04

5.14.2 L1/L4 troubleshooting

Step 1: Check the DC voltage between P and N terminal, the normal value should be 510V~580V, if the
voltage is lower than 510V, go to step 2.
Step 2: Check whether the wires of rectifier circuit are loose or not. If wires are loosen, fasten the wires. If
wires are OK, replace the PCB.
3-Phase
rectifier stack

5.14.3 L2 troubleshooting

Step 1: Check the DC voltage between P and N terminal, the normal value should be 510V~580V, if the
voltage is higher than 580V, go to step 2.
Step 2: Check the voltage between two electrolytic capacitors, the normal value should be 510V± 30V or
310V± 30V, if not in the range then the Main board has malfunction, it needs to be replaced.
Troubleshooting
Filter
Single-Phase
rectifier stack board
Turn the measure
range of the meter to
1kV and measure the
voltage between two
electrolytic capacitors
R410A DC Inverter V4 Plus 50Hz
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