baipin
New Member
- Joined
- Dec 25, 2020
- Messages
- 68
Having a problem with a used MS2812. It powers a load or remains in search for about 10 seconds then powers itself off until DC input is removed or the inverter is reset. The guy who sold it to me said all was functional and the only maintenance work done to it was having the main board replaced by Magnum/Sensata through Tiffen Motorhomes (it came out of an Allegro motorhome I believe).
The inverter's green LED will blink once when connected to DC as it should (connected to a 12V battery; I have tried with both LiFePO4 and FLA). It will then power on briefly when I press the ON/OFF button beside the LED. If I power it on with no AC load, I will hear a clicking noise from what sounds like right in the transformer; not the relays as far as I can tell. What could possibly be inside a transformer to cause clicking?! It then goes silent and nothing happens when I press the power button again, until I either remove DC input or I hold the button on the inverter for 15 seconds to poerforma soft-reset. If I power the inverter on and then immediately turn on my AC load, the clicking stops, and the load receives power (I tried this with a 10W lightbulb and a 60W lightbulb) for 10 seconds. If I power the invert on, then wait 5 seconds to turn on the AC load, the clicking from the transformer continues for those first 5 seconds without AC load. Once AC load is switch on, then the AC load remains on for 5 more seconds until 10 seconds is up, at which point the inverter shuts itself off and must be reset. I noticed throughout all of this, there is a red, yellow, and green LED lit up on the control board. I believe that all should be lit up and if the yellow one is not, then there is a temperature problem. So according to the LEDs, it's functioning normally.
I have a video describing these issues here: New video by BlPlN
Pay attention to 1:39. The mic on my phone is pretty awful but you can just barely hear the *click click click click...* until about 1:47 when the inverter shuts itself off and must be reset.
Note that the voltage of the LiFePO4 battery was at 14.0V, the FLA battery was at 12.5V, and I was drawing 5A at 12VDC and outputting 0.5A at 120VAC with the 60W lightbulb, which means my 1 ft run of 10AWG should be sufficient. Correct polarity was always observed.
I noticed some suspicious things on this inverter to begin with; the screw terminals on the factory-installed side of the wiring had the screws applied to the insulation of the wires, not the actual copper!! There are witness marks only on the insulation; suggesting it came this way from the Magnum factory, and even when the repairs were made, this was not touched. It's just by pure luck that some copper touched the inside of the screw terminal. On one of the big 1 AWG crimp connections coming off of the FETs, there were a couple loose wires sticking out and near the case. Yeah it's only a few strands, but that's enough to cause a short (and these wires could be carrying 300A)!! I'm pretty shocked by the shoddy workmanship - I'd of expected better from Magnum. This was obviously from the factory like this; no reason those cables would of been replaced. For the crimp connectors that go between the AC board (the one that was replaced) and the transformer's temperature sensors, half the crimps were made on unstripped, insulated wire and not even in the crimp section of the butt splice, but in the strain relief part you're not supposed to crimp!
Note that the crimp is finished after where I cut this, meaning the only crimped section was an insulated one. I suppose it's possible they fed both ends of the wire into the same end of the butt splice, but why would they mangle the strain relief? That doesn't really make much sense since replacement boards come with one end (in the pic below, the lower white wire) pre-crimped, and it doesn't look like this:
Finally, one of the 3-inch long standoffs to hold this board was found rolling around, beneath the FETs (fortunately, it is not made of a conductive material) and an entire 3.5" long screw is nowhere to be found. Here is what one of the three out of four remaining screws looks like:
I'm under the impression there was some shoddy work done when this MS2812 Magnum inverter was first built, and when repairs were done, allegedly under warranty by Magnum themselves.
I purchased this from someone on Facebook Marketplace and have written confirmation that they would take it back if it did not work for any reason. I swear I'm following the correct procedure to test this inverter out:
Some help with this would be much appreciated.
The inverter's green LED will blink once when connected to DC as it should (connected to a 12V battery; I have tried with both LiFePO4 and FLA). It will then power on briefly when I press the ON/OFF button beside the LED. If I power it on with no AC load, I will hear a clicking noise from what sounds like right in the transformer; not the relays as far as I can tell. What could possibly be inside a transformer to cause clicking?! It then goes silent and nothing happens when I press the power button again, until I either remove DC input or I hold the button on the inverter for 15 seconds to poerforma soft-reset. If I power the inverter on and then immediately turn on my AC load, the clicking stops, and the load receives power (I tried this with a 10W lightbulb and a 60W lightbulb) for 10 seconds. If I power the invert on, then wait 5 seconds to turn on the AC load, the clicking from the transformer continues for those first 5 seconds without AC load. Once AC load is switch on, then the AC load remains on for 5 more seconds until 10 seconds is up, at which point the inverter shuts itself off and must be reset. I noticed throughout all of this, there is a red, yellow, and green LED lit up on the control board. I believe that all should be lit up and if the yellow one is not, then there is a temperature problem. So according to the LEDs, it's functioning normally.
I have a video describing these issues here: New video by BlPlN
Pay attention to 1:39. The mic on my phone is pretty awful but you can just barely hear the *click click click click...* until about 1:47 when the inverter shuts itself off and must be reset.
Note that the voltage of the LiFePO4 battery was at 14.0V, the FLA battery was at 12.5V, and I was drawing 5A at 12VDC and outputting 0.5A at 120VAC with the 60W lightbulb, which means my 1 ft run of 10AWG should be sufficient. Correct polarity was always observed.
I noticed some suspicious things on this inverter to begin with; the screw terminals on the factory-installed side of the wiring had the screws applied to the insulation of the wires, not the actual copper!! There are witness marks only on the insulation; suggesting it came this way from the Magnum factory, and even when the repairs were made, this was not touched. It's just by pure luck that some copper touched the inside of the screw terminal. On one of the big 1 AWG crimp connections coming off of the FETs, there were a couple loose wires sticking out and near the case. Yeah it's only a few strands, but that's enough to cause a short (and these wires could be carrying 300A)!! I'm pretty shocked by the shoddy workmanship - I'd of expected better from Magnum. This was obviously from the factory like this; no reason those cables would of been replaced. For the crimp connectors that go between the AC board (the one that was replaced) and the transformer's temperature sensors, half the crimps were made on unstripped, insulated wire and not even in the crimp section of the butt splice, but in the strain relief part you're not supposed to crimp!
Note that the crimp is finished after where I cut this, meaning the only crimped section was an insulated one. I suppose it's possible they fed both ends of the wire into the same end of the butt splice, but why would they mangle the strain relief? That doesn't really make much sense since replacement boards come with one end (in the pic below, the lower white wire) pre-crimped, and it doesn't look like this:
Finally, one of the 3-inch long standoffs to hold this board was found rolling around, beneath the FETs (fortunately, it is not made of a conductive material) and an entire 3.5" long screw is nowhere to be found. Here is what one of the three out of four remaining screws looks like:
I'm under the impression there was some shoddy work done when this MS2812 Magnum inverter was first built, and when repairs were done, allegedly under warranty by Magnum themselves.
I purchased this from someone on Facebook Marketplace and have written confirmation that they would take it back if it did not work for any reason. I swear I'm following the correct procedure to test this inverter out:
Some help with this would be much appreciated.