Panel setup

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jjwitty

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Location
Indianapolis
Occupation
Automation
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I have a question for guys that do panel builds. I’m exploring different ways to go about setting this panel up that controls 18 motors. I’m using combo motor starters, using feeder blocks and bus bars, all in attempt to have less wires and parts.

Do you believe duct is needed between line out to motor and terminal block ? Looking at it, it seems unnecessary.

Now I have from the bottom up:
1. Duct
2. Terminal block
3. Motor starters
4. Duct
5. Starters
6. Duct
7. Power distribution.

I also am having some extra space after using these starters, so I am thinking how I could set out up for more controls later.

I am also thinking of having a bank of 10 terminal blocks for L1, 10 for L2, 10 for L3, and 10 for ground. You see in the bottom I have all the jumpers installed. I’ve never saw this done before, I’m wondering if this would be a bad idea as far as safety. I realize the terminal jumpers are meant for 30 amps max, so I am going to need to reduce the amount. Other than that, can’t see any reason not to wire the motors this way.

https://imgur.com/a/1Ro9W5M
 
I would not use terminals downstream of the contactor. Let them wire direct to the contactor. Saves space, and eliminates a crap load of connections that can fail. Plus the terminals have sccr problems, as in they are typically not going to match the rest of the circuit. With the type F starters they are usually 65kA but the terminals kick the circuit back to 5 or 10 kA.

I see no purpose in the ten terminals of each phase.

I typically use multiport lugs for ground connections and just bolt them to the panel. The green terminals expensive.

Screenshot_20241019-004742.png
 
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These multi lugs are a pain to find. I looked on McMasters and was only able to find a couple sizes for 1-14. Rest was 1-750.
 
petersonra said:
Lugsdirect.com
Click to expand...
I’m removing the second row of terminal blocks, adding duct above the terminal blocks on bottom.

It will go:
1. Duct
2. Terminal block
3. Duct
4. Motor starter
5. Duct
6. Motor Starter
7. Duct
8. Power

Thank you for bring SCCR. The TB Sccr was lost in this design.
 
If you have any wiring going from the panel to the door I would suggest using MTW. The insulation has the flexibility needed for repeated opening and closing of the door without damage to the insulation over time.
 
I wired many panels using this type of layout.

Yes adding field terminal strips introduces a potential failure point, however having all of the field connections in a common entry location prevented installers from creating 'rats nests' of wiring which often makes troubleshooting and servicing of the panels difficult. The decision is about weighing the pros and cons.
 
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petersonra said:
I would not use terminals downstream of the contactor. Let them wire direct to the contactor. Saves space, and eliminates a crap load of connections that can fail. Plus the terminals have sccr problems, as in they are typically not going to match the rest of the circuit. With the type F starters they are usually 65kA but the terminals kick the circuit back to 5 or 10 kA.

I see no purpose in the ten terminals of each phase.

I typically use multiport lugs for ground connections and just bolt them to the panel. The green terminals expensive.

View attachment 2573945
Click to expand...
Yeah, I don’t see the point in terminal blocks below the motor contactors in a control panel like this. What’s the difference between using those terminals vs basically the same terminals on the contactors? It gains you nothing, but adds more potential points of failure.

You can bet power terminals with higher SCCR values, but usually they need to be protected by fuses. So now you have to add ANOTHER device!
 
Jraef said:
Yeah, I don’t see the point in terminal blocks below the motor contactors in a control panel like this. What’s the difference between using those terminals vs basically the same terminals on the contactors? It gains you nothing, but adds more potential points of failure.

You can bet power terminals with higher SCCR values, but usually they need to be protected by fuses. So now you have to add ANOTHER device!
Click to expand...
I need the terminal blocks for the coils at least. There also steam control I need to wire into terminal blocks. 9 of the motors, the bottom row, will be controlling heat exchangers.
 
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