Received 480VAC Panel instead of 208VAC

scc851

Member
Location
Toronto
Occupation
Control Tech
Hey Guys,

As said in the title, we recently purchased a new control panel that controls a hydraulic system at our facility (pump, 3Ph motor, solenoids and everything was included in the package from the panel builder).

We requested a 208VAC panel since we already had a distribution panel nearby where we could add the extra breaker for the new panel and running the electrical supply would be simple. The quote the panel builder supplied has 208VAC listed in the panel specs as its input Voltage.

Unfortunately we opened the crate earlier and we noticed that the panel was designed for 480VAC. We called the manufacturer and they basically told us not to worry that the panel would still work. The answer we received from the technical assistance desk was very quick so I have my doubts about his answer.

I just wanted to run this by you guys. I'm new to this job and I don't want to challenge the panel builder/designer without checking a few things.

- By supplying a lower voltage to the panel won't we need more current (Almost Double) to meet load? Therefore wouldn't this mean the breakers would be undersized?
- Also, since more current would be needed. Shouldn't the wires be a larger gauge? It looks like thje wire Gauge is 14AWG so I think we should be fine since it's a pretty small pump.
- The 24VDC power supply is rated for a input range of 400-500VAC. If we're only supplying 208VAC the power supply won't be functioning correctly.
- Also, the panel they supplied is supposed to be UL Certified. I would assume by changing the input power, the certification would not apply.

For us to supply 480VAC to this panel would take a lot more work, and if this is the case were probably going to ask them to supply what we ordered or ask them to pay for the extra electrical labour.

Any advice would be greatly appreciated.
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector
You can use the 480v panel on 208v systems with no changes. Breaker sizes, wire sizes, etc will not change.
The panel voltage is a "max". Using one at a lower voltage is fine.


Disregard! (I'm glad growler was here).. I mis-read or didn;t completely read...I thought you were talking about a panelboard (breaker panel) sorry... listen to growler :)
 
Last edited:

growler

Senior Member
Location
Atlanta,GA
We requested a 208VAC panel .

Unfortunately we opened the crate earlier and we noticed that the panel was designed for 480VAC. We called the manufacturer and they basically told us not to worry that the panel would still work.

- The 24VDC power supply is rated for a input range of 400-500VAC. If we're only supplying 208VAC the power supply won't be functioning correctly.


Any advice would be greatly appreciated.
I wouldn't hook this thing up just because someone on the phone says it will work. I have had people lie to me in the past.

If the manufacturer says it will work they should be able to provide information on how and why it's supposed to work. Did they install a multi tap transformer in this panel that will accept different inputs? Is there a schematic or diagram showing this will work with a 208V input?

I would call the manufacturer and ask to speaker with someone more knowledgeable such as an engineer. Unless the provided the correct paperwork.
 

growler

Senior Member
Location
Atlanta,GA
You can use the 480v panel on 208v systems with no changes. Breaker sizes, wire sizes, etc will not change.
The panel voltage is a "max". Using one at a lower voltage is fine.
What about supplying that DC power supply with a voltage lower than rating?
 

scc851

Member
Location
Toronto
Occupation
Control Tech
I wouldn't hook this thing up just because someone on the phone says it will work. I have had people lie to me in the past.

If the manufacturer says it will work they should be able to provide information on how and why it's supposed to work. Did they install a multi tap transformer in this panel that will accept different inputs? Is there a schematic or diagram showing this will work with a 208V input?

I would call the manufacturer and ask to speaker with someone more knowledgeable such as an engineer. Unless the provided the correct paperwork.
I agree. I'll have to ask my boss if he has a project contact or ask for written confirmation that the panel will work with 208VAC. Because from what I'm seeing stuff isn't adding up in this panel and I don't want to be responsible any damage.

No they did not install a multi tap transformer in the panel. The panel is very straight foward. 480VAC going directly through breakers then supplies power to our motor circuit by going through fuses, contactors and overloads. Then suplies power to the 3 phase motor.

For the controls basically we have the 480VAC supplying power to our 24VDC PS and that supplies power to a small PLC.
 

winnie

Senior Member
Location
Springfield, MA, USA
Occupation
Electric motor research
Using 480V components such as breakers and the like at 208V is perfectly fine as long as they are sized properly for the load.

It sounds like several pieces of this hardware are not suitable for 208V however, and the manufacturer needs to make a few changes to meet spec.

Jon
 
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