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Bababoee
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Discussion Starter · #1 ·
Is it allowable to have a generator supply two different loads from seperate power sources..? I have police radio equipment for one load and a verizon site for the other load. Both are fed from two different power sources. Is it ok to have a seperate transfer switch for the police radio..
 

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captkirk said:
Is it allowable to have a generator supply two different loads from seperate power sources..? I have police radio equipment for one load and a verizon site for the other load. Both are fed from two different power sources. Is it ok to have a seperate transfer switch for the police radio..
. That's a good one ! Legally , per NEC , I would say that's not a problem , but are there 2 different services coming in ? If it's a police station , that's my guess . Off of different grids , so they always have a backup . What happens , if both normal grids go down and the one generator doesn't start ? A lot of what ifs , but it's a great question .
 

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As long as both transfer switches are open transition (break before make), it shouldn't be a problem. Each switch should send an independent start signal to the generator anyway, even if they are fed from the same utility source.
 

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Bababoee
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Discussion Starter · #10 ·
Originally the PD wanted to use power from the Verizon Hut. Its like a big shed that houses the Verizon equipment and there is a fenced in the area where the tower is the PD installed some radio equipment that's probably uses like 400 watts but verizon did not want them tapping off of their power so we had to go across this large field to a 480 panel to which I brought power converted it to 240 120 for the police radio gear.
Verizon is installing a propane generator 50 kW for their gear and the PD ask them if they could power they're radio equipment on their generator for an emergency situation. It's pretty ridiculous when you look at the amount of work I have to do to get there power over there for their measly 400 watts.
My apologies for the typos using text to talk
 

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Originally the PD wanted to use power from the Verizon Hut. Its like a big shed that houses the Verizon equipment and there is a fenced in the area where the tower is the PD installed some radio equipment that's probably uses like 400 watts but verizon did not want them tapping off of their power so we had to go across this large field to a 480 panel to which I brought power converted it to 240 120 for the police radio gear.
Verizon is installing a propane generator 50 kW for their gear and the PD ask them if they could power they're radio equipment on their generator for an emergency situation. It's pretty ridiculous when you look at the amount of work I have to do to get there power over there for their measly 400 watts.
My apologies for the typos using text to talk
I make more typos then anyone else. And its on a desk top computer:laughing::eek:


Anyway, I can see this being an issue if the genset fails. There is no assurance to the PD that Verizon will properly maintain said genset or refuel it during an extended outage. If it fails the PD will have Verizon to blame, and good luck putting responsibility on a behemoth company.

Locally it may not be allowed if for example during an emergency power needs to be cut to the structure. I would imagine the AHJ may want a label saying alternate power is coming from the version hut. So in an emergency personal may have to travel to the Verizon hut to kill power. NEC does not have an issue with this as far as I know, but local safety codes might say otherwise.

Plus, if this equipment is mission critical, do you really want to bargain with a company that is technically not responsible?


This might help: http://www.kohlerpower.com/onlinecatalog/pdf/g4213.pdf
 

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Bababoee
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Discussion Starter · #12 ·
I make more typos then anyone else. And its on a desk top computer:laughing::eek:


Anyway, I can see this being an issue if the genset fails. There is no assurance to the PD that Verizon will properly maintain said genset or refuel it during an extended outage. If it fails the PD will have Verizon to blame, and good luck putting responsibility on a behemoth company.

Locally it may not be allowed if for example during an emergency power needs to be cut to the structure. I would imagine the AHJ may want a label saying alternate power is coming from the version hut. So in an emergency personal may have to travel to the Verizon hut to kill power. NEC does not have an issue with this as far as I know, but local safety codes might say otherwise.

Plus, if this equipment is mission critical, do you really want to bargain with a company that is technically not responsible?


This might help: http://www.kohlerpower.com/onlinecatalog/pdf/g4213.pdf
I installed a portable connection port as well so they can plug in a small honda inverter type gen. It was set up to be just a portable gen hook up but when they found out Verizon was installing a big standby they wanted in.
 

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I installed a portable connection port as well so they can plug in a small honda inverter type gen. It was set up to be just a portable gen hook up but when they found out Verizon was installing a big standby they wanted in.
If reliable back up isn't a concern then it can be done. I don't know of NEC caring. However just check with the AHJ just in case they have "fire fighter rules".
 

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Can't Remember
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I am curious as to how this would be wired. Can this be wired as an either or setup? Assuming this is a two wire start, will a two wire transfer switch transfer if it sees both utility and generator power?
 

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I installed a portable connection port as well so they can plug in a small honda inverter type gen. It was set up to be just a portable gen hook up but when they found out Verizon was installing a big standby they wanted in.
If Verizon wouldn't let them use their utility service, what made them think they'd allow them to use their backup generator?
 

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I installed a portable connection port as well so they can plug in a small honda inverter type gen. It was set up to be just a portable gen hook up but when they found out Verizon was installing a big standby they wanted in.
We have several other providers on out emergency comm. towers they are responsible for their on power and back up power. The PD will find that it will be cheaper to have you install a small 11 or 15 Kw air cooled unit than go through all of the crap with 2 ATS's.
 

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I am curious as to how this would be wired. Can this be wired as an either or setup? Assuming this is a two wire start, will a two wire transfer switch transfer if it sees both utility and generator power?
If the engine is a 2 wire start it can have as many ATS as needed. Most hospitals and some office complexes will have one or more large genets with multiple ATS through out the facility tapping off the emergency conduits. Any one ATS sensing a loss of power will short the 2 wire engine start circuit. Once the generator starts all the ATS will have emergency power available.

The genset in the version building will need to feed into a panelboard and have 2 breakers, one for the version hut the other feeding the conduit over to the PD center. Both ATS engine start contacts will be in parallel so any one calling for power will start the generator.
 

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Can't Remember
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I have only one two wire start generator that I work on, Pow'r Gard AE8, the rest being Generac and Briggs. So, no matter what, when the board in the transfer switch sees generator power, it'll transfer to generator power, even if there is utility available?
 

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meadow said:
My thinking is if both have separate utility sources I would imagine 2 separate structures along with separate owner ship. Sounds as though the police station needs a back up for something as well as the Verizon tower.
. This was my point . Too much liability if Verizon's standby system doesn't start , if you ask me . Nothing worse than a blacked out police station looking to the EC as to what went wrong , lol .
 

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Bilge Rat
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One of the casinos I work at once in a while has 4 generators, 17 transfer switches and two POCO feeds. The POCO feeds come from different substations.

If the normal side of any transfer switch loses power, all 4 gens will start and synch together (most of the time.....). They will continue to run until all switches have returned to normal feed.

You could put 100 transfer switches on one gen if you want, and as long as the gen can handle the total load, it'd be legal.

The only place where you need to watch switches and gens is life-safety systems (hospitals and such). Otherwise, it's pretty much open-season.
 
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