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PTO Generators Observations
I have been doing research on this topic and it would seem that we are all ignorant in this area. This topic is one of much debate among electritians trying to install generator hookups that are up to code. The BIG differences are opinions on the neutral (should it be switched at the transfer switch or not) and whether or not to bond the neutral to ground. The code distinguishes between generators that are SDS (separately derived system) or not and that is one of many factors that determines whether the neutral is switched. There are also factors that determing whether a generator should be grounded or not. In most cases it is actually MORE dangerous to ground a portable (not permanently installed) generator. I have reread the posts in this thread and it seems to me that the opinion that comes closest to code for a PORTABLE (this would include PTO and all carted generators and may even include some of the larger generac systems) generator is as follows:
Install a transfer switch that switchs L1 and L2 but NOT neutral. Do NOT ground the generator with a grounding rod and make sure that neutral is NOT bonded to ground at the generator. A good site with tons of info by people who do this for a living is provided in the link.
Link:
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PTO Generators Observations
Denwood, pulling an electric meter is considered tampering and is against the law. If you notice there is a colored wire seal attached to the meter base that you must cut to remove the meter. the purpose of this seal is to indicate to the utility that an un-authorized person had access to the meter base. This is the utilities source of revenue and they are very protective. We prosecute for tampering with the service.
Additionally, it is very dangerous if you don't use the proper equipment. Not only can the meter glass break but a lug could break and cause a short circuit resulting in a flash burn. People have been seriously hurt, you can have 5000 to 10,000 amps of available fault current at the meter base. Saving the cost of a service call could end up costing alot more in the long run. Dave
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PTO Generators Observations
AB, you are getting very close, there are risks of grounding a portable genset, it is safer to use the neutral to ground the genset into the house system. It is NOT, however, safe to leave the neutral connected back to the grid from the house when the house is being back-fed by a genset. There is a very real risk of creating a potential in the neutral and causing a hazard for anyone working on the supposedly dead wires in the grid.
KY, a very good point about meter tampering, although I would think the bigger hazard would be from taking the meter off it's base and having all those live leads open to anyone who wanders by.
Best of luck.
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PTO Generators Observations
I didn't really mean you personally should pull the meter, the licensed electrician that did my install pulled the meter. As far as him getting in trouble, that is on him, although I can tell you that PECO seems pretty laid back about the whole thing, but maybe they are not. Too schedule a shutoff takes several days as does getting it turned back on, very inconvenient trying to schedule an electrician and power company at the same time and to have minimal down time.
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According to my relative, the professional engineer who builds power plants, the way to pull the meter is to smash the glass on the meter and tell the power company you have been vandalized. Then pull the meter. If you do things the "right" way - you will never get the job done. You have to schedule a shutdown with the power company - and the electrical inspector simultaneously. Then the power company comes and shuts power down - but doesn't wait for job to be done to turn power back on. They come back a few days later to turn power back on - and you are without power for a few days - not worth the effort.
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Also - my relative was smart enough to install a switch between the meter and his fuse box so that he would never have this problem when he built his house. I wish I had such a switch in my house!
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Ncruch32, your engineer friend needs to read the Engineer's Code of Ethics, and review the oath he took when he accepted his license. His attitude is a disgrace to the profession.
With my company, you can schedule a disconnect for first thing in the morning with a reconnect prior to quiting time. That is provided your electrician (and passes inspection) can complete the job within the time frame. We take pride in being responsive to the needs of the customer and do our best to work with them.
Depending on the location and accessibility of the distribution panel a main service disconnect maybe required, ref NEC art. 230.70, between the meter and distribution panel. Dave
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Kyvette, your response is expected  I certainly don't think my BIL actually has ever smashed any glass since he is the honest type and is a church elder. He was speaking hypothetically. However I do know that he has handled the live wires coming into a house rather than bother calling the power company to shut the power off. He carefully inserts a block of wood between the hot leads and tapes the wires around the leads and the block. He would rather risk his life than bother calling the power company. (I know that this will evoke even more response!)
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PTO Generators Observations
No so Murf. The factor that determines whether to switch neutral in the transfer switch is related to how the generator is wired internally and grounded externally. In fact with certain generators, (mostly portable types including PTO driven generators) "backfeeding" of the neutral is required by the NEC (code). If the generator is a floating neutral generator (neutral not bonded to frame) then neutral must NOT be switched at the transfer switch. In this configuration the generator system uses the service neutral and associated bonding with the GEC (Grounding electrode conductor)at the service panel to to ground the neutral (zero volt reference) and a switched neutral will open that connection resulting in an ungrounded EGC (equipment grounding conductor) and floating neutral. If the generator has neutral bonded to the frame then a transfer switch that switches neutral is required. The generator is now required to have its own separate grounding electrode conductor (grounding rod). In short: No bond between frame and neutral on the generator (floating neutral) = use a transfer switch that does not switch neutral. If neutral is bonded to the frame, use a transfer switch that switches ground and install a separate ground rod.
Read the posts on generators at the link below, there are several, some have circuit diagrams that are very helpful.
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Ann, with all due respect, I think you need to re-read my post and the link I posted.
I said "... there are risks of grounding a portable genset, it is safer to use the neutral to ground the genset into the house system. It is NOT, however, safe to leave the neutral connected back to the grid from the house when the house is being back-fed by a genset.".
I did not, nor did I intend to, say that the house & genset should NOT BE grounded. To open the neutral without leaving an adequate ground for the system would be foolish, and an open invitation for electrocution and or a fire.
What I was trying to get across was that there is a very real danger in leaving the neutral connected back to 'the grid'.
The only safe way to do it would be to have the service panel grounded directly such that when the neutral is opened the system is still grounded.
When the NEC was written it was not worded with the proliferation of gensets that we have today in mind.
Here in Canada, where the electrical safety regulations are amongst the strictest in the world, NOT opening the neutral back to the grid is a violation.
Best of luck.
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