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Posted By: George Little Generac Generator Wiring - 11/19/07 11:59 AM
Does anyone have a comment on the wiring method used to connect the battery charger and interlock wiring between the generator and the transfer switch? Let me explain- The transfer switch (200a. Service rated) is located about 100 feet the generator. The transfer switch has overcurrent protection integral with the switch. There is a 240v. fuse block located within the transfer switch and this is used to supply the battery charger located in the generator enclousure. There is a 24v. circuit between the generator and the transfer switch used to trigger a relay an hence the transfer of power. I think the 24v. power source is in the generator. I say "I think" because I have not been able to get much information from Generac. So my question is: What wiring method would I expect to see for this installation? The installation in question has a run of SER for the load and CL2 18/4 for the 240v. battery charger circuit and the 24v. interlock circuit.
I believe the CL2 would be suitable for the relay interlock wiring if the circuit were Class 2 but I think the 240v. circuit would require an equipment grounding conductor and should not be wired with CL2 cable. I apologize for the length of this post but Hey! you want details don't you?
Posted By: gfretwell Re: Generac Generator Wiring - 11/19/07 04:41 PM
CL2 is only good for class 2 725 circuits if I read 725.61 right. If this comes from a listed class 2 supply (<30v limited current) and the cable is isolated from line voltage conductors I would say it was OK. Otherwise I think I would want to see an article 725 class 1 wiring method, which looks substantially like chapter 3 wiring methods.
Posted By: earlydean Re: Generac Generator Wiring - 11/19/07 08:37 PM
725.52 allows Class 2 or 3 circuits to be installed as Class 1 circuit IN THEIR ENTIRETY. Which would also allow them to be in the same enclosure as line voltage.
Posted By: George Little Re: Generac Generator Wiring - 11/20/07 02:03 AM
Dean- I saw that and I would have no problem with it if the installation were not installed using CL2 cable run along side the SER cable This would not give me the wiring method of Chapter 3. I would say NM cable or any of the metal jacketed cables or EMT would be compliant. Also, unless I'm mistaken, I would need a grounding conductor.

Part of the problem is the Classification of the circuits. The manufacturer is very difficult when it comes to supplying information.
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