Hi All 

 

With all the load-shedding and the need for long battery life, we opted against ups for our data centre and went the inverter route.

We have been running perfectly fine but recently we have had issues with power as the only transformer left in our area is very problematic. 

When we have an outage everything stays up except for one machine that reboots. This has now spread to a Cisco switch also in the same room feeding from the same DB.

Note there is only one source of power and it comes from the inverter to the room.

 

This morning we had such an instance and the only information I got from the electrical chaps is we had an overvoltage in the area.

I am completely stumped as to what is causing this. If wverything went down I'd say yes its the inverter but only one/two devices ?

 

Please help

1 minute ago, williet said:

Hi All 

 

With all the load-shedding and the need for long battery life, we opted against ups for our data centre and went the inverter route.

We have been running perfectly fine but recently we have had issues with power as the only transformer left in our area is very problematic. 

When we have an outage everything stays up except for one machine that reboots. This has now spread to a Cisco switch also in the same room feeding from the same DB.

Note there is only one source of power and it comes from the inverter to the room.

 

This morning we had such an instance and the only information I got from the electrical chaps is we had an overvoltage in the area.

I am completely stumped as to what is causing this. If wverything went down I'd say yes its the inverter but only one/two devices ?

 

Please help

very strange indeed - could it be that their power supplies are older and more sensitive to power / voltage fluctuations? 

5 minutes ago, mzezman said:

very strange indeed - could it be that their power supplies are older and more sensitive to power / voltage fluctuations? 

If all other circuits in the premises are ok. Could be just something like a bad connection in that specific circuit? 

Thats what I was thinking. First it was a dell server and now a cisco switch has also started these shenanigans.

I wonder if solarman dongle has snmp capabilities to chart power.

I have gor it spread between two breakered circuits with other devices sharing those breakers with no problems.

10 minutes ago, williet said:

Note there is only one source of power and it comes from the inverter to the room.

Weird, the inverter power should be nice and clean and stable. Does the inverter have enough capacity and battery power?

3 minutes ago, Antonio de Sa said:

something like a bad connection in that specific circuit? 

I had a similar issue many years ago, turned out to be on the db where the one breaker was not torqued in correctly, that slight "looseness" caused havoc.

16 minutes ago, WannabeSolarSparky said:

Weird, the inverter power should be nice and clean and stable. Does the inverter have enough capacity and battery power?

Hi 

 

Yes. Two 10kw sunsynk batteries with an 8kw inverter drawing a load of 3kw+-

The only time I have seen issues with a setup like that was when we forgot there was an old rackmount UPS with those devices still connected to it, seems they dont like having an inverter feed a UPS before hitting the devices. 

Straight feed should be fine though, I have plenty of servers and Cisco AP's/switch gear on inverters at various clients and havent had an issue with any of them.

 

15 minutes ago, RocketBoy said:

The only time I have seen issues with a setup like that was when we forgot there was an old rackmount UPS with those devices still connected to it, seems they dont like having an inverter feed a UPS before hitting the devices. 

Straight feed should be fine though, I have plenty of servers and Cisco AP's/switch gear on inverters at various clients and havent had an issue with any of them.

It is very strange. It seems to be happening with older equipment eg 6 year old dell and a five year old switch with redundant power supplies.

Unlike UPSs, the inverter is not on-line.  It actually has a change over relay which must switch when the grid is out of spec.

This change should be less than 10ms, but in this period, no power is supplied to the loads.

All electronic devices should be able to survive such a short outage, but capacitors degrade with age, so sometimes old equipment can't even survive the 10ms change over.

Easiest option is to replace the power supply on affected devices.

23 minutes ago, JustinSchoeman said:

Unlike UPSs, the inverter is not on-line.  It actually has a change over relay which must switch when the grid is out of spec.

This change should be less than 10ms, but in this period, no power is supplied to the loads.

All electronic devices should be able to survive such a short outage, but capacitors degrade with age, so sometimes old equipment can't even survive the 10ms change over.

Easiest option is to replace the power supply on affected devices.

Makes sense. IT PSU's on the devices are the oldest in the room.