ethnobotanica
New member
Hi Everybody,
We've bumped into a rather large problem at our nursery which may cause us to undoo about 10k worth of work...which we would rather not, which may be easily solved by a simple code.
Basically, we did a bunch of unpermitted electrical work a little while ago. The problem part, is that we installed 10 or so DPDT relays, to squeeze more poser out of our service. These DPDT relays were used to move lighting loads from one area to another, for different shifts, allowing us to expand both work areas by separating the shifts. This works great. A contractor did the work (unpermitted), and the world was a beautiful place full of great unpermitted work.
That is until our fire inspector noticed all the unpermitted work....here comes the building inspector...and next thing you know we are having to get permits (better then a red-tag no doubt, and lesson learned).
So back to those relays, which are the problem. Each relay allows us to switch 240v/30a between 2 loads. Both loads CANNOT be energized at the same time, so only 30a max can be used (actually each relay is on a 20a breaker running appx 14a) Problem is, which the electrical engineer sat down to do the calculations, she had never worked with relays of this nature. As far as she can find there is no code section that allows to derate the consumption by 50% with the relays, or the maximum on one side of the relay. Instead, she believes we have to calculate the load as if all equipment was on at the same time.
Is this true? Alternatively is there a code that allows to show that the equipment is on the relay so to only calculate the load on each side of the relay?
Seems unrealistic that we would have to calculate the load based on an impossible electrical load of everything being charged at once, seeing as both loads cannot be on at the same time. This doubles our load and puts us over our service limits.
Thanks,
Ryan
We've bumped into a rather large problem at our nursery which may cause us to undoo about 10k worth of work...which we would rather not, which may be easily solved by a simple code.
Basically, we did a bunch of unpermitted electrical work a little while ago. The problem part, is that we installed 10 or so DPDT relays, to squeeze more poser out of our service. These DPDT relays were used to move lighting loads from one area to another, for different shifts, allowing us to expand both work areas by separating the shifts. This works great. A contractor did the work (unpermitted), and the world was a beautiful place full of great unpermitted work.
That is until our fire inspector noticed all the unpermitted work....here comes the building inspector...and next thing you know we are having to get permits (better then a red-tag no doubt, and lesson learned).
So back to those relays, which are the problem. Each relay allows us to switch 240v/30a between 2 loads. Both loads CANNOT be energized at the same time, so only 30a max can be used (actually each relay is on a 20a breaker running appx 14a) Problem is, which the electrical engineer sat down to do the calculations, she had never worked with relays of this nature. As far as she can find there is no code section that allows to derate the consumption by 50% with the relays, or the maximum on one side of the relay. Instead, she believes we have to calculate the load as if all equipment was on at the same time.
Is this true? Alternatively is there a code that allows to show that the equipment is on the relay so to only calculate the load on each side of the relay?
Seems unrealistic that we would have to calculate the load based on an impossible electrical load of everything being charged at once, seeing as both loads cannot be on at the same time. This doubles our load and puts us over our service limits.
Thanks,
Ryan
