Securing back feed circuit breaker

[retiredguarddog]

I am in the early stages of putting up a 4.1 KW grid tied system. I talked with the state electrical inspector and he mentioned that the NEC required that all back feed circuit breakers to be secured in the panel. I talked with my local utility (Wyrulec) and they are trying to find such a device. There have only been two other renewable energy systems in their area and are not sure where to find something like this. Wouldn't the normal faceplate that covers the breakers do the same thing? It is a Siemens box and breakers. I would hate to come to the end and not be able to connect because of a technicality.

[Naptown]

must be on the 2002 code 2011 does not require this.

[SunEagle]

I am in the early stages of putting up a 4.1 KW grid tied system. I talked with the state electrical inspector and he mentioned that the NEC required that all back feed circuit breakers to be secured in the panel. I talked with my local utility (Wyrulec) and they are trying to find such a device. There have only been two other renewable energy systems in their area and are not sure where to find something like this. Wouldn't the normal faceplate that covers the breakers do the same thing? It is a Siemens box and breakers. I would hate to come to the end and not be able to connect because of a technicality.

Are you sure he said the Main panel or just a panel. They may not want to have someone just hang a circuit breaker on a piece of wood with the wires exposed.

You are allow to create a bus tap from one panel to another as long as the cables being used as the tap are at least 1/3 the ampacity of the panel bus and are 10 ft or less.

You might want to get clarification concerning the back feed cb.

[Naptown]

Are you sure he said the Main panel or just a panel. They may not want to have someone just hang a circuit breaker on a piece of wood with the wires exposed.

You are allow to create a bus tap from one panel to another as long as the cables being used as the tap are at least 1/3 the ampacity of the panel bus and are 10 ft or less.

You might want to get clarification concerning the back feed cb.

Huh?

[SunEagle]

Huh?

Sorry. I'm just tired. I may not always write down clearly what I am thinking.

If there is not more space in the main panel to install the back feed circuit breaker he should be able to terminate the circuit to a breaker in a separate box. Then run cables between this box and the main panel tapping to the main panels bus bars.

Depending on the amperage of his back feed circuit he doesn't necessarily need wires rated as high as the main panels bus bars such as a 200amp house panel. They have to be rated for a least 70 amps even if his back feed circuit breaker is only 50 amps. The cable lengths also can't be longer than 10 feet to adhere to the 10 ft tap rule in the NEC.

[sirsparky]

hold down retainer clip

The latest revision of the NEC article 690 specifically states that you do NOT need to secure a solar backfeed breaker with a hold down retainer clip.
However, you have to follow what the local inspector/jurisdiction wants.

Contact the breaker manufacturer sales/technical rep.
Most breaker manufacturers make a hold down retainer clip that is designed to secure the breaker. You field install this device to restrain the
breaker securely in place.

[inetdog]

The latest revision of the NEC article 690 specifically states that you do NOT need to secure a solar backfeed breaker with a hold down retainer clip.
However, you have to follow what the local inspector/jurisdiction wants.

Contact the breaker manufacturer sales/technical rep.
Most breaker manufacturers make a hold down retainer clip that is designed to secure the breaker. You field install this device to restrain the
breaker securely in place.

There are sections in the NEC which place requirements on all circuit breakers which feed power into the bus bars of a panel which are more strict than the requirements for circuit breakers that draw power from the bus. The concern is that breakers which are feeding power in would remain hazardous voltage sources if they became disconnected from the bus. The 2011 code recognizes that although the inverter normally feeds power into onto the bus, it does not represent a source of hazardous voltage once it has become disconnected. The anti-islanding circuitry in a GTI prevents that. The concern is for what might happen when the dead-front cover over the breakers has been removed for troubleshooting, measurement, etc.

NEC 2011 408.36(D):

(D) Back-Fed Devices. Plug-in-type overcurrent protection devices or plug-in type main lug assemblies that are backfed and used to terminate field-installed ungrounded supply conductors shall be secured in place by an additional fastener that requires other than a pull to release the device from the mounting means on the panel.

[Naptown]

Actually with an off grid or stand alone system the breaker must be secured as off grid inverters do not shut down as a grid tie would.
but one end of that or both is still going to be live until the inverter is shut down in that case

[SunEagle]

Not paying attention to question

Naptown

I again apologize for my earlier answers to the original question. For some reason I though it had to do with not having enough space in the main panel to install the back feed breaker.

Now I understand it has to do with physically securing that breaker with an additional strap of some kind.

I appreciate your patience with me.

Vince

[retiredguarddog]

settled

I guess that pretty much settles where it came from. now all I have to do is find a source for one. Solar is pretty rare around here and no one knows much about where to get things for it. Any ideas?

There are sections in the NEC which place requirements on all circuit breakers which feed power into the bus bars of a panel which are more strict than the requirements for circuit breakers that draw power from the bus. The concern is that breakers which are feeding power in would remain hazardous voltage sources if they became disconnected from the bus. The 2011 code recognizes that although the inverter normally feeds power into onto the bus, it does not represent a source of hazardous voltage once it has become disconnected. The anti-islanding circuitry in a GTI prevents that. The concern is for what might happen when the dead-front cover over the breakers has been removed for troubleshooting, measurement, etc.

NEC 2011 408.36(D):

[Naptown]

Google is your friend.
try the term "Siemens circuit breaker retaining clip. "

[retiredguarddog]

it worked

It worked, assuming that it will work on smaller breakers, (30 amp) I can now breathe easier knowing that I can please the state inspector. Thanks for all the help to all of you.

Google is your friend.
try the term "Siemens circuit breaker retaining clip. "

[PaulDickerson]

2011 NEC 705.12(D)(6) allows the additional fastener to be omitted for backfeed breakers connected to utility interactive inverters. If you show your inspector this code section he probably will agree that it is not needed. If he still wants it, they are cheap and easy to install.

[dougdstecklein]

I know this is an old thread but I wanted to thank Paul for sharing the NEC code that allows additional fasteners to be omitted.
My inspector stated that I need a 2nd means of attachment for my solar backfed breakers so I have been searching multiple electrical supply stores with no luck. I found out that GE does not make breaker retainers for the combiner panel I used, so I was going to have to redo my combiner box and all the wiring in it. I brought the 2011 NEC 705.12(D)(6) code to the attention of my inspector and he agreed that the breaker retainers were not required in this situation. I passed inspection this morning.

[peakbagger]

Home Power Coder Corner this month discusses when and when no retainer is needed.