Infrared inspection for electrical problems

[Brian A. MacNeish]

Just read another members website promoting IR here's what it says:

From these temperature variances I can report probable issues with things like: insulation, water infiltration, air infiltration, electrical problems, the presence of vermin, and more

How are persons claiming residential electrical problem inspections without loading all breakers/fuses, wiring, junctions, switches, receptacles, motors, etc to do a full electrical inspection?

I find this misleading as it is a mere fluke to find anything without some to full current draw on all circuits and devices.

[John McKenna]

How do you know if he did it wrong?

[Kevin A. Richardson]

Originally Posted by Brian A. MacNeish

Just read another members website promoting IR here's what it says:

From these temperature variances I can report probable issues with things like: insulation, water infiltration, air infiltration, electrical problems, the presence of vermin, and more

How are persons claiming residential electrical problem inspections without loading all breakers/fuses, wiring, junctions, switches, receptacles, motors, etc to do a full electrical inspection?

I find this misleading as it is a mere fluke to find anything without some to full current draw on all circuits and devices.

Not a fluke....here are two examples:

The first image is a 15 amp fuse that was overloaded. It measured at 13 amps.

The second image is a dimer switch that measured between 127 and 130 degrees F (at face plate). Dimers are usually hotter than a normal switch due to internal resistance, but this particular dimer controlled 8 can lights. All from this one dimer switch.

Rather be safe and call out both issues than be sorry

Kevin

[Chuck Lambert]

Originally Posted by Brian A. MacNeish

From these temperature variances I can report probable issues with things like: insulation, water infiltration, air infiltration, electrical problems, the presence of vermin, and more

.

I have more of a problem with this statement than any other.

[William Warner]

Originally Posted by Chuck Lambert

I have more of a problem with this statement than any other.

Why?

Rodent burrows in ceiling insulation show up quite nicely!

Rodents and other mammals produce heat and show up quite nicely as well!

[bdoles2]

Originally Posted by Chuck Lambert

I have more of a problem with this statement than any other.

Why...I came across this a few weeks ago. 2 squirrels in an interior wall cavity, and yes I was the one to remove them.

See it here

[David A. Andersen]

Brian, evaluating electrical circuits with infrared should be loaded to 30% minimum for evaluation.

For the most part turning on all the lights in the house and after running appliances (stoves, ovens, microwave, dishwasher, refrigerator, HVAC, water heater (the electric) generally gets most circuits up to that capacity. That's less than 5 amps on a 15 amp circuit.

It doesn't take very much to find an electrical issue with the infrared camera. The important thing is to evaluate the temperature in comparison to the amperage draw on the circuit at the time of testing. Even at a low load, defective devices show up warm.

If you have a circuit breaker at 90° at a 70° ambient panel temperature and you only have 6 amps on a 15 amp breaker, I think it's safe to say there are issues to investigate further.

[Chuck Lambert]

Originally Posted by wwarner

Why?

Rodent burrows in ceiling insulation show up quite nicely!

Rodents and other mammals produce heat and show up quite nicely as well!

I guess I see more electrical problems than squirrel problems. Fortunately in Southern California there are not that many squirrels, now rats are a different story!

[John McKenna]

Where did Brain go?

[John McKenna]

Originally Posted by krichardson

Not a fluke....here are two examples:

The first image is a 15 amp fuse that was overloaded. It measured at 13 amps.

The second image is a dimer switch that measured between 127 and 130 degrees F (at face plate). Dimers are usually hotter than a normal switch due to internal resistance, but this particular dimer controlled 8 can lights. All from this one dimer switch.

Rather be safe and call out both issues than be sorry

Kevin

I love your images. Very nice camera.

[Dominic J. Maricic]

Originally Posted by Chuck Lambert

I guess I see more electrical problems than squirrel problems. Fortunately in Southern California there are not that many squirrels, now rats are a different story!

Move up to Arrowhead Lived up there for 10 years. Plenty of Squirrel problems! Like them always eating the food from my bird feeders, or running INTO the house and up my leg!


Brian,
That's an awesome IR photo. Amazing that they had nested in INTERIOR walls!

[William R. DeVries, CMHI]

Originally Posted by Brian A. MacNeish

Just read another members website promoting IR here's what it says:

From these temperature variances I can report probable issues with things like: insulation, water infiltration, air infiltration, electrical problems, the presence of vermin, and more

How are persons claiming residential electrical problem inspections without loading all breakers/fuses, wiring, junctions, switches, receptacles, motors, etc to do a full electrical inspection?

I find this misleading as it is a mere fluke to find anything without some to full current draw on all circuits and devices.

During the inspection all lights would normally be turned on to test ? Yes
I leave them on and continue inspecting
last inspection is electric panel and branch circuts after visual I then pop out the Bcam and have a lookise, if i see any anomolies then I go room to room and scan areas, if I see something out of ordinary I refer to electrical contractor for futher eval and include IR photo A call to my electrician friend and he can in most cases be right there in a few hours. Sellers do not mind buyers do not mind and issues are or can be resolved that day.

Now I have not run into vermin as of yet but did find a ceiling not insulated due to squirrels, but they were dead in the attic, damage was already done

[Brian A. MacNeish]

Originally Posted by dandersen

Brian, evaluating electrical circuits with infrared should be loaded to 30% minimum for evaluation.

Are we talking about electrical circuits and devices throughout the house or just the service entrance / panels and circuit overload protection?

In the far extremes of a circuit, if you had a bad connection that produced a resistance of say 10 Ohms, here's the way it may play:
With a .5 amp draw, the heat generated would be 2.5 Watts (P= I squared x R). At the point far away from the panel, would you be able to pick up that heat. If the current increased to 1 amp, the heat would be 10 Watts. If it increased to 8 amps by other lights and receptacles on the circuit being used, the heat would now be 640 Watts........enough to cause a glowing connection and a fire!!!

http://glowingconnection.com/

http://www.springerlink.com/content/lwh56537056v515u/

http://adsabs.harvard.edu/abs/1976STIN...7719352M

I would think that to properly say an IR electrical inspection was done all receptacles should be individually loaded and scanned. If there was a nicked wire in a wall or box, it may not heat up until a large enough amperage load was running through it.

For the most part turning on all the lights in the house and after running appliances (stoves, ovens, microwave, dishwasher, refrigerator, HVAC, water heater (the electric) generally gets most circuits up to that capacity. That's less than 5 amps on a 15 amp circuit.

It doesn't take very much to find an electrical issue with the infrared camera. The important thing is to evaluate the temperature in comparison to the amperage draw on the circuit at the time of testing. Even at a low load, defective devices show up warm.

If you have a circuit breaker at 90° at a 70° ambient panel temperature and you only have 6 amps on a 15 amp breaker, I think it's safe to say there are issues to investigate further.

Have to careful on creating expectations!!!

[Brian A. MacNeish]

Originally Posted by krichardson

Not a fluke....here are two examples:

The first image is a 15 amp fuse that was overloaded. It measured at 13 amps.

Kevin:

How do you figure a fuse designed to blow at 15 amps was overloaded at 13 amps? Yes, the intent of code for regular house circuits is to design them so as to not draw more than 80% of wire rating hence a #14 AWG wire should not carry more than 12 amps- a 20% safety factor, theoretically!!

The second image is a dimer switch that measured between 127 and 130 degrees F (at face plate). Dimers are usually hotter than a normal switch due to internal resistance, but this particular dimer controlled 8 can lights. All from this one dimer switch.

Rather be safe and call out both issues than be sorry

Kevin

127 -130 degrees F is the delivery air temp of most forced warm air furnaces. The blowers usually come on at 150 degrees and safety "off" is 200 degrees F. Was this temp of just 30 degrees above body temp really a problem?

[Kevin A. Richardson]

Kevin:

How do you figure a fuse designed to blow at 15 amps was overloaded at 13 amps? Yes, the intent of code for regular house circuits is to design them so as to not draw more than 80% of wire rating hence a #14 AWG wire should not carry more than 12 amps- a 20% safety factor, theoretically!!

You asked a question, then in the same paragraph, provided the answer. A circuit that is above 80% of rating will always get written up for further evaluation by a Licenced Electrician. If an Electrician comes behind me and certifies the circuit to be fine, then so beit! I sleep better at night knowing I did my job.

127 -130 degrees F is the delivery air temp of most forced warm air furnaces. The blowers usually come on at 150 degrees and safety "off" is 200 degrees F.

This is an odd statement. Your comparing apples to oranges. Execessive heat in "electrical" components = potential trouble. period.

Was this temp of just 30 degrees above body temp really a problem?

By most standards, yes. At the very least it warrants further evaluation!! And, the reference is from "ambient temp" NOT "body temp."

Kevin