Electrical Panels thermography

[jado85]

All,

I have been asked to figure out what/and how to improve thermography on electrical panels without the need to open them, I believe I found a suitable product that will allow thermal imaging and not require additional PPE or opening the panels.
now my question is what components should I be interested in monitoring my list so far:

1. fuses
2. breakers
3. terminal strips
4. ...

or should I inspect all of the components in the panels? if so I thought I could install a large square Window that has a larger viewing area and place enough to be able to see all the components.

If you have other thoughts or suggestions please let me know.

Thank you,
Jad,

 

[Bugman1400]

You cannot perform a thermography inspection on panel without taking the cover off unless you have an inspection window that is rated for arc-flash. IOW, you can't just cut a hole and put a piece of plexi-glass in place.

 

[ron]

add conductor terminations

 

[jado85]

Ahh the Arc flash rating was an easy way to sort the panels that need infrared window, I also now realize that the CB on the switchgear are visible to the infrared camera which means I don't need the infrared window for those.
http://www.iriss.com/vpfr

IRISS has a product that monitor the temperature difference inside and outside the panel, do you think that such device will be able to perhaps detect trouble inthe panel? does the conductors in the panel emit enough heat to cause a temperature difference?

 

[kwired]

Ahh the Arc flash rating was an easy way to sort the panels that need infrared window, I also now realize that the CB on the switchgear are visible to the infrared camera which means I don't need the infrared window for those.
http://www.iriss.com/vpfr

IRISS has a product that monitor the temperature difference inside and outside the panel, do you think that such device will be able to perhaps detect trouble inthe panel? does the conductors in the panel emit enough heat to cause a temperature difference?

It is normal for overcurrent devices to put off heat, it is normal for conductors to put off heat. A temp sensor in the cabinet will not tell you if you have equal rise on all three lines (say we just have a three pole fused disconnect) or if one connection happens to be producing more heat then it should, all it tells you is a temperature setpoint has been reached.

 

[jado85]

It is normal for overcurrent devices to put off heat, it is normal for conductors to put off heat. A temp sensor in the cabinet will not tell you if you have equal rise on all three lines (say we just have a three pole fused disconnect) or if one connection happens to be producing more heat then it should, all it tells you is a temperature setpoint has been reached.

The goal is to be alerted to that change in panel temperature and have someone inspect it, instead of relying on the semi annual thermography. Can you think of any hazard(fire) causing faults that will not produce heat?

Being new to the industry, I'm asking a lot of question, thank you all for being patient and helpful!

 

[don_resqcapt19]

I expect that you could have a heat producing problem that could result in a catastrophic failure without tripping a panel temperature alarm. You can produce a lot of localized heat without making a large change in the panel temperature.

 

[kwired]

The goal is to be alerted to that change in panel temperature and have someone inspect it, instead of relying on the semi annual thermography. Can you think of any hazard(fire) causing faults that will not produce heat?

Being new to the industry, I'm asking a lot of question, thank you all for being patient and helpful!

Enclosure with fixed load running through it maybe has better chance of having consistent temperature, if load varies - I think this is total waste of time. If ambient temp of space where the cabinet is located varies it doesn't help with consistency any either.

Thermo image will quickly point out a hot spot in it's early stages of failure, and give you some time to plan for repair/replacement. Temp sensor in the cabinet may not indicate a problem until it is at the point it needs replaced immediately.

JMO, and I imagine one can find exceptions to what I mentioned

 

[jado85]

Enclosure with fixed load running through it maybe has better chance of having consistent temperature, if load varies - I think this is total waste of time. If ambient temp of space where the cabinet is located varies it doesn't help with consistency any either.

Thermo image will quickly point out a hot spot in it's early stages of failure, and give you some time to plan for repair/replacement. Temp sensor in the cabinet may not indicate a problem until it is at the point it needs replaced immediately.

JMO, and I imagine one can find exceptions to what I mentioned

I understand your point, My thought is if I can detect some of the problems, it might be worth it.
here is a link to the product, http://www.iriss.com/deltat

 

[jado85]

are there recommended schedule for thermal inspection for switchgears, switchboards..etc?

 

[Bugman1400]

are there recommended schedule for thermal inspection for switchgears, switchboards..etc?

Typically once a year when the current flow is at its highest.

 

[big john]

While I absolutely respect the desire to think outside the box and come up with new and different solutions, I don't think there is a way to accomplish this.

I do PM for a living and have done a lot of thermography: You simply can't find high temperature faults without a covers-off survey. Any other method is just guessing.

It's not uncommon for a severe failure to have a >100°C temperature difference when compared to a similar component located 6 inches away; the heating can be extremely localized.

 

[Tony S]

While I absolutely respect the desire to think outside the box and come up with new and different solutions, I don't think there is a way to accomplish this.

I do PM for a living and have done a lot of thermography: You simply can't find high temperature faults without a covers-off survey. Any other method is just guessing.

It's not uncommon for a severe failure to have a >100°C temperature difference when compared to a similar component located 6 inches away; the heating can be extremely localized.

I’ve got to agree with you there.

With the covers on you may detect a general temperature rise “somewhere” in the cubical. To find the actual point of the temperature rise the covers have to come off so why take them off it in the first place.

Thermographic checks have found a few faults on switchgear for us. The worse being a 1250A 11KV breaker that had it failed would have taken out ¼ of the works.

They are worth doing but only if done properly.

 

[iwire]

With the covers on you may detect a general temperature rise “somewhere” in the cubical. To find the actual point of the temperature rise the covers have to come off so why take them off it in the first place.

I am not disagreeing with your point only commenting on the hesitation to remove the covers.

For the past 10 or 15 years the enforcement of long established rules regarding what we would call live work has been greatly increased.

Large fines are being handed out to companies for violating these rules. The result of that has been companies adopting very strict policies regarding the removal of covers with the equipment energized. Often these private policies go beyond what the governmental rules require.

So what may have been common in the past has now become taboo with mountains of paperwork to fill out, waiting times and steps to take before I can open a cover just to take a look.

Again, I am not disagreeing with the need to open the covers just trying to explain the reason it is happening less and less.

 

[ActionDave]

I am not disagreeing with your point only commenting on the hesitation to remove the covers.

For the past 10 or 15 years the enforcement of long established rules regarding what we would call live work has been greatly increased.

Large fines are being handed out to companies for violating these rules. The result of that has been companies adopting very strict policies regarding the removal of covers with the equipment energized. Often these private policies go beyond what the governmental rules require.

So what may have been common in the past has now become taboo with mountains of paperwork to fill out, waiting times and steps to take before I can open a cover just to take a look.

Again, I am not disagreeing with the need to open the covers just trying to explain the reason it is happening less and less.

So what we need from now on is just to have everybody do four years in the Army.

 

[zog]

We install a lot of these in high value critical system switchgear, 24/7 monitoring. Typically we use thermal monitors in LV switchgear and PD monitors in MV gear.

http://www.intellisaw.com/Technology/intellisaw-critical-asset-monitoring-system.html

 

[jado85]

We install a lot of these in high value critical system switchgear, 24/7 monitoring. Typically we use thermal monitors in LV switchgear and PD monitors in MV gear.

http://www.intellisaw.com/Technology/intellisaw-critical-asset-monitoring-system.html

I came across this system a few days ago, why do you go with PD for MV gear?how many sensor are you using per switch?

I also realized that installing the IR window will have to be done by the manufacturer to maintain the warranty and UL rating, also on certain bran, there is a door interlock that is directly in front of the fuses blocks the installation of an IR window. It wouldn't make sense to be able to test 5/6 points on the switch, therefor I think either an active system or do nothing on the switch gears.

 

[zog]

I came across this system a few days ago, why do you go with PD for MV gear?how many sensor are you using per switch?

PD is a more common failure mode in MV systems, sometimes used along with IR sensors. # of sensors all depends on criticallity and configuration of the equipment.

 

[jado85]

PD is a more common failure mode in MV systems, sometimes used along with IR sensors. # of sensors all depends on criticallity and configuration of the equipment.

I'm seriously considering intellisaw system for our plant, and have contacted a sales person for info.
I do have some question I'd like to ask you as a user of that system, I hope you don't mind answering.
I'm considering installing PD/temp sensor in Switchgears, MCC..(basically equipment we can't inspect with IR without interruption)

Did you have any unexpected difficulties installing the system and providing a power source within the equipment, and did you have to alter the enclosure of the switchgear to feed in communication cables. any tips and recommendations

 

[moonshineJ]

If the whole cubicle panel were made out of this IR-grade glass then it would have much more sense. Some year ago I had to remove a front steel cover to take temp readings from all six terminals of 600 A molded case circuit breaker using a thermal imager. One was JUST 2 degrees hotter than the rest; no weird bright colors, just a 2 deg difference in digital readouts. Upon removal the breaker we saw that the corresponding hole in copper bus was badly pitted leaving probably less than 20% of useful contact area with the breaker's stud. And it was some occasionally chattering relay (getting power from that affected phase) that drawn attention.
I think such a small inspection port just won't cover all areas of interest for thermography.