Author Topic: Newbie Install. "Straight-In" mains question...  (Read 5102 times)

daveydoo

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Newbie Install. "Straight-In" mains question...
« on: July 19, 2015, 02:05:34 AM »
My home has this circuit breaker panel:

http://www.homedepot.com/p/Square-D-Homeline-200-Amp-40-Space-40-Circuit-Outdoor-Surface-Mount-Main-Breaker-Combination-Service-Entrance-Device-SC40M200S/100127276

It says it has "straight-In mains". When I open the panel and look at what connects to the main circuit breaker I see two metal bars. That differs from the diagram in the installation manual and youtube videos and pictures I've seen of what the incoming phase A and B power lines are suppose to look like (two fat, thickly insulated cables). Are those two metal bars what I should be attached the CTs to?

Also a second issue I have is connecting the black wire of the MTU to a circuit breaker. I don't have any spare circuit breakers. Do I need to install a new circuit breaker and attach the wire to it? Or can I just piggyback off a circuit breaker already being used?

thanks

« Last Edit: July 19, 2015, 04:10:02 AM by daveydoo »

pfletch101

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Re: Newbie Install. "Straight-In" mains question...
« Reply #1 on: July 19, 2015, 03:16:12 AM »
My home has this circuit breaker panel:

http://www.homedepot.com/p/Square-D-Homeline-200-Amp-40-Space-40-Circuit-Outdoor-Surface-Mount-Main-Breaker-Combination-Service-Entrance-Device-SC40M200S/100127276

It says it has "straight-In mains". When I open the panel and look at what connects to the main circuit breaker I see two metal bars. That differs from the diagram in the installation manual and youtube videos and pictures I've seen of what the incoming phase A and B power lines are suppose to look like (two fat, thickly insulated cables). Are those two metal bars what I should be attached the CTs to?

As you probably realize, you need to place the main CTs round the main current feeds, rather than attaching them to the feeds, and this is likely to be quite difficult with the breaker box layout that you have. There is an alternate type of CT which is much more flexible, but you still need to be able to wrap it round the current feeds, so you have to be able to get behind them (after removing power from them, which is probably another issue with your layout).

Quote
Also a second issue I have is connecting the black wire of the MTU to a circuit breaker. I don't have any spare circuit breakers. Do I need to install a new circuit breaker and attach the wire to it? Or can I just piggyback off a circuit breaker already being used?

I would recommend either giving the MTU its own (new) dedicated circuit breaker, or attaching it to the breaker that feeds the socket into which you are going to be plugging the ECC, assuming that that breaker is designed to accept two separate wire connections.
Peter R. Fletcher
TED Pro Home - main MTUs monitoring utility and PV Solar feeds; 2 Spyders monitoring selected individual circuits

daveydoo

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Re: Newbie Install. "Straight-In" mains question...
« Reply #2 on: July 19, 2015, 04:40:35 AM »
Thanks for that info. Very helpful.

I updated the pictures in the original post. You can see the metal bars that I need to get around. I confirmed that I am NOT able to attach the 200A CTs that came with my TED Pro around them--the bars are too wide. But I think these CTs should be able to get around (and behind) the bars (which are about 20-21mm in diameter):

https://www.theenergydetective.com/400amplarge.html

So if I wanted to go forward with this I would I just need to buy two of these large 400A CTs and assuming they fit I am good to go? Also you said I would need to turn off the power to those metal bars. Is that step for safety reasons because the bars are exposed and not insulated? If one were extremely cautious could the CTs be installed around the bars without shutting off power to the powerline bars?

-dave

pfletch101

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Re: Newbie Install. "Straight-In" mains question...
« Reply #3 on: July 19, 2015, 06:07:24 AM »
Thanks for that info. Very helpful.

I updated the pictures in the original post. You can see the metal bars that I need to get around. I confirmed that I am NOT able to attach the 200A CTs that came with my TED Pro around them--the bars are too wide. But I think these CTs should be able to get around (and behind) the bars (which are about 20-21mm in diameter):

https://www.theenergydetective.com/400amplarge.html

So if I wanted to go forward with this I would I just need to buy two of these large 400A CTs and assuming they fit I am good to go?

I was actually thinking of the flexible CTs which now only appear to be available (in very high current versions) for the Pro Commercial series - I thought that I had seen that you could get 400A versions of these for the Pro Home, but I could well have been imagining this.  Assuming that the 400A clamp-on ones that you identify do fit, you should not have a problem.

Quote
Also you said I would need to turn off the power to those metal bars. Is that step for safety reasons because the bars are exposed and not insulated? If one were extremely cautious could the CTs be installed around the bars without shutting off power to the powerline bars?

My caution was for safety, and because I was thinking of the flexible CTs. The clamp-on ones should be able to be applied with care to live bars, though I would not want to go on record as recommending this!  :)
Peter R. Fletcher
TED Pro Home - main MTUs monitoring utility and PV Solar feeds; 2 Spyders monitoring selected individual circuits

at

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Re: Newbie Install. "Straight-In" mains question...
« Reply #4 on: July 21, 2015, 02:02:01 AM »
I had thick wires and used the 400amp CTs.  Worked fine.  But before around those posts, they are live.  Be sure to turn them off before you get near them.

pfletch101

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Re: Newbie Install. "Straight-In" mains question...
« Reply #5 on: July 21, 2015, 05:06:17 AM »
But before around those posts, they are live.  Be sure to turn them off before you get near them.

I think that the OP's problem may be that he can't turn off the power feeding those bars without involving the utility company.
Peter R. Fletcher
TED Pro Home - main MTUs monitoring utility and PV Solar feeds; 2 Spyders monitoring selected individual circuits

kherr

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Re: Newbie Install. "Straight-In" mains question...
« Reply #6 on: September 25, 2015, 11:06:15 AM »
Call the power co. and tell them you want the meter pulled for 5 minutes tops. They will be more than willing to help you. You don't want to see what a 200 amp short looks like, not to mention you'll be DEAD .... They won't want to deal with the aftermath either ...

pfletch101

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Re: Newbie Install. "Straight-In" mains question...
« Reply #7 on: September 25, 2015, 05:45:26 PM »
Call the power co. and tell them you want the meter pulled for 5 minutes tops. They will be more than willing to help you. You don't want to see what a 200 amp short looks like, not to mention you'll be DEAD .... They won't want to deal with the aftermath either ...

It may be as simple as that - it may not. Anecdotally, at least, some utilities are very co-operative with customers who want temporary power shutdowns for this sort of purpose; others are anything but!
Peter R. Fletcher
TED Pro Home - main MTUs monitoring utility and PV Solar feeds; 2 Spyders monitoring selected individual circuits

jfpetesn

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Re: Newbie Install. "Straight-In" mains question...
« Reply #8 on: September 25, 2015, 06:35:30 PM »
Around here we cut the seal, pull the meter ourselves and then call the power company to reseal it.

pfletch101

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Re: Newbie Install. "Straight-In" mains question...
« Reply #9 on: September 26, 2015, 02:45:38 AM »
Around here we cut the seal, pull the meter ourselves and then call the power company to reseal it.

Are you a licensed electrician? I ask, not because I think that pulling the meter requires any special skill or knowledge, but because I can imagine a utility company taking a reasonably friendly view of an electrician pulling the meter in the course of a project at a customer's house while taking a very dim view of the customer doing/having done it.
Peter R. Fletcher
TED Pro Home - main MTUs monitoring utility and PV Solar feeds; 2 Spyders monitoring selected individual circuits

jfpetesn

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Re: Newbie Install. "Straight-In" mains question...
« Reply #10 on: September 26, 2015, 05:52:56 AM »
No live in a rural community so I guess they are more lenient.  Happens all the time.  They don't really know what one does.  All they know is the seal is broken or missing. I had one seal broken for several years before anyone noticed.  If you cut it right next to the plastic tab and bend it back in place they may never know.  No harm no foul in my opinion.  No real need to hire an expensive electrician for such a quick and simple installation.

I will also say that they would never use this type of service panel around here.  I wouldn't want my service panel located on an exterior wall where anyone could get to it.  Prefer mine within my residence and under my complete control.
« Last Edit: September 26, 2015, 06:01:35 AM by jfpetesn »