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Does anyone know how to defeat the door interlock on Square D HVL switches?
if you are near the switch could you please post a pic

Sent from my HUAWEI Y210-0100 using Tapatalk 2
 

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I noticed that it's easier to open the back of the cabinet than the door. :whistling2:
Unless their is a switch on the back that opens the switch when you remove a panel.
 

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Discussion Starter · #7 ·
jrannis said:
I noticed that it's easier to open the back of the cabinet than the door. :whistling2:
Unless their is a switch on the back that opens the switch when you remove a panel.
You can't see the fuse holders from the back. It's also much safer to swing a hinged door open than to wrestle a heavy 7' tall cover near energized 13.8 busswork.
 

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Thermography.
I don't think you are going to see anything looking in the front.
Do you suspect a problem or is this a routine activity?
Do you have a tie breaker in the gear lineup where you can switch the load to another side and de- energize the side you are working on?
You are into distribution voltage with it being 15k plus in there, I would think that you would have another substation on the other end to switch to.
With the switch de energized. You could still pick up a hot spot after shutting down for a few minutes.
 

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Discussion Starter · #9 ·
jrannis said:
I don't think you are going to see anything looking in the front.
Do you suspect a problem or is this a routine activity?
Do you have a tie breaker in the gear lineup where you can switch the load to another side and de- energize the side you are working on?
You are into distribution voltage with it being 15k plus in there, I would think that you would have another substation on the other end to switch to.
With the switch de energized. You could still pick up a hot spot after shutting down for a few minutes.
A lot of our customers use HVL lineups for campus distribution. These are typically radial systems without a second source. It would be impossible to open the switches one at a time and try to catch any kind of normal load (too much disruption to the process).
 

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Sorry, You won't be able to open to door when it's energized.

If you gear doesn't have a separate little comet glass porthole with the special " inspection glass" in it, you should insist that they make this modification.
This isn't the regular plastic fuse viewing window, it comes with a specific type of glass that will allow an infrared inspection.

If there is a way to open that door, I don't think you are going to get someone to tell you about it on a public forum.
 

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Damn right I won't :rolleyes:

Also, I second the idea to intall IR windows, super cheap and easy to do, we install hundreds per year.
 

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If you are just looking to take a shot or two of the fuse holders, simple shut the gear down. It will not possibly lose enough heat to adversely affect your study. When I do this type of cubicle “study”, I am generally looking for temperature DIFFERENCES (as in loose fuse holders, etc…), not absolute temperatures.

Open the switch, open the cubicle, take the shot(s), close it up, turn it back on, move to the next one. If you can’t turn it off for some reason, don’t do the study. Interlocks are there for a reason.

But that's just me.
 

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Usually here, pad mounts have boots over the primary.

We had 10 -13.8 kv USS on one job with cast core 1000s that were open that had bolt on covers.
Those could be opened and inspected...
 

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Discussion Starter · #15 ·
jrannis said:
Usually here, pad mounts have boots over the primary.

We had 10 -13.8 kv USS on one job with cast core 1000s that were open that had bolt on covers.
Those could be opened and inspected...
I always hate pulling the covers off of those. The bus is usually so close to the opening.
 

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I always hate pulling the covers off of those. The bus is usually so close to the opening.
Our you could of look into through the expanded metal and see what ever you ended to inspect.
I have some pics of a burn spot on one of them that we changed.
I don't think it really had a problem but they let the transfer company haul lit off as scrap.
 

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Discussion Starter · #18 ·
jrannis said:
Our you could of look into through the expanded metal and see what ever you ended to inspect.
I have some pics of a burn spot on one of them that we changed.
I don't think it really had a problem but they let the transfer company haul lit off as scrap.
You must have a different model than what I'm used to seeing. All the dry type unit subs I've worked on had solid metal covers with the exception of the ventilation louvers near the floor. There certainly were no expanded metal sections where someone could stick something inside the transformer section. :eek:
 

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You must have a different model than what I'm used to seeing. All the dry type unit subs I've worked on had solid metal covers with the exception of the ventilation louvers near the floor. There certainly were no expanded metal sections where someone could stick something inside the transformer section. :eek:
I just saw some dry type in Dallas that were open like that. They were only 4160 but made enough noise to be uncomfortable.
 
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