MPPT is not taking load due to MPPT backplanes are faulty in MPPT product
Step 1: Check MPPT LED Status
Check visual condition of MPPT module:
Verify LED indication:
- LD LED → should glow
- COM LED → should glow/blink
Result
- If LEDs glowing and MPPT taking load → System OK
- If LEDs not glowing → proceed to next step
Step 2: Check Communication Cable and Connections
Inspect communication wiring:
✔ Check communication cable connection
✔ Ensure cable properly inserted
✔ Check connector tightness
✔ Verify no loose wiring
Result
- If communication issue found → correct wiring
- Recheck MPPT status
Step 3: Check MPPT Input MCB Voltage
Measure voltage at MPPT input MCB.
Voltage Range Requirement
| Customer | Voltage Range |
|---|---|
| Indus | 90V – 350V |
| RJio | 70V – 350V |
Voltage range is mentioned on MPPT sticker.
Step 4: Check Polarity of MPPT Input
Verify correct polarity of solar input wiring:
| Terminal | Connection |
|---|---|
| Positive (+) | Positive wire |
| Negative (-) | Negative wire |
⚠ Common Issue:
Technician sometimes connects reverse polarity in MCB.
Action
Correct polarity if wiring is reversed.
Step 5: Check MPPT Load Status After Correction
Result
- If MPPT taking load → Issue resolved
- If MPPT still not taking load → check hardware slot
Step 6: Swap MPPT Module Slot
Move MPPT module to another working slot.
Action
- Remove MPPT module
- Insert into known working slot
- Check MPPT load status
Step 7: Identify Faulty Component
Result
-
If MPPT works in new slot
→ Backplane faulty -
If MPPT still not working
→ MPPT module faulty
Step 8: Provide Trouble Ticket (TT)
Part Codes
| Customer | Part Code |
|---|---|
| Indus | 305200225C |
| RJio | 307294815C |
Provide TT with required spare part.