I have a problem thats causing some head scratching. Large old factory divided up into smaller units and sub let. Mixture of light industrial, storage, offices & a gym. I have been told of problems a short while ago when tenants complained of flickers in the supply, the DNO came & said they would have to dig up the road but they did not, although after their visit apparently the supply improved drastically. I have to assume they simply tightened up all their connections.
This week a few tenants have complained again about fluctuations in the supply. One office has said there computers are now crashing a few times a day due to this. Their servers are ok as they are on a UPS which is showing it has been activated every time they look.
The supply is TP & N 100A PME. Main switchfuse feeds a busbar chamber, then into various switchfuses and landlords check meters then onto the units own distribution boards. Although most units have a 3 phase supply, only 1 has any 3 phase equipment, this is an engineering company with large presses, bench drills etc.
The DNO came again yesterday who said there is nothing wrong on their side, but as the supply was not turned off i dont know how they can claim this.
I thought it must be a loose connection, possibly the neutral so today we did a total shutdown and went through every single connection at the distribution ( this took 2 hours). No loose connections or signs of arcing, overheating was found. We also checked the boards in the offices and found nothing. We checked the voltages & did a Ze (cant remember the figures) but all was acceptable. The seal fairy really had been so we checked even all those connections.
After we had finished, the offices IT guy, who also rents a unit upstairs said he has not had a problem but described a buzzing sound for fractions of a second coming from the office DB when the power flickers. This appears to be random, the DB is an old TP &N with rewirable fuses. No breakers or electronics.
I have not been into the engineering unit yet, but am trying to work out if they have say a loose connection somewhere could this be causing harmonics on the supply ? grabbing at straws here.
Any ideas ???
This week a few tenants have complained again about fluctuations in the supply. One office has said there computers are now crashing a few times a day due to this. Their servers are ok as they are on a UPS which is showing it has been activated every time they look.
The supply is TP & N 100A PME. Main switchfuse feeds a busbar chamber, then into various switchfuses and landlords check meters then onto the units own distribution boards. Although most units have a 3 phase supply, only 1 has any 3 phase equipment, this is an engineering company with large presses, bench drills etc.
The DNO came again yesterday who said there is nothing wrong on their side, but as the supply was not turned off i dont know how they can claim this.
I thought it must be a loose connection, possibly the neutral so today we did a total shutdown and went through every single connection at the distribution ( this took 2 hours). No loose connections or signs of arcing, overheating was found. We also checked the boards in the offices and found nothing. We checked the voltages & did a Ze (cant remember the figures) but all was acceptable. The seal fairy really had been so we checked even all those connections.
After we had finished, the offices IT guy, who also rents a unit upstairs said he has not had a problem but described a buzzing sound for fractions of a second coming from the office DB when the power flickers. This appears to be random, the DB is an old TP &N with rewirable fuses. No breakers or electronics.
I have not been into the engineering unit yet, but am trying to work out if they have say a loose connection somewhere could this be causing harmonics on the supply ? grabbing at straws here.
Any ideas ???
hms , dunno what happens if its over this, but I do know DNO came out and made sure we had the required path when they were informed of the requirements.
