Portable radio tripping GFCI

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102 Inspector

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N/E Indiana
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Inspector- All facets
One of our firefighters has had issues with the portable radio tripping a GFCI receptacle when he is within 3 feet of the device. The radio is not even transmitting, just on. The radio is an 800 megahertz VHF radio. I have told him to place the radio near the kitchen circuit and see if it does it to all the circuits. Currently he says it impacts 2 circuits that he knows of. Is there any reason why this would be occuring? It does not happen all the time, very random. Thank you.
 
102 Inspector said:
One of our firefighters has had issues with the portable radio tripping a GFCI receptacle when he is within 3 feet of the device. The radio is not even transmitting, just on. The radio is an 800 megahertz VHF radio. I have told him to place the radio near the kitchen circuit and see if it does it to all the circuits. Currently he says it impacts 2 circuits that he knows of. Is there any reason why this would be occuring? It does not happen all the time, very random. Thank you.
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What kind of radio is it?

Is it a Motorola, Kenwood, Icom or a Chinese cheapie?
 
Here is a video of a portable radio tripping a GFCI while transmitting.


That was a Baofeng (Chinese) radio. But still, the radio had to be transmitting.

Edit to add:

I just tried the same thing with my Yaesu FT-50RD dual band ham radio. It actually did trip one of the GFCI's I tested it on. But, only if I transmitted. I even made it legal and transmitted my ID.

Also, I had to have the antenna (same kind as in video, a higher gain add on) touching the receptacle. It wouldn't trip if I was even a few inches away.
 
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This a Motorola radio and he indicates that he is not transmitting when it trips the device. Normally he places his radio on the dresser and the GFCI in the adjacent bathroom actually trips. Approx. 18" away directly line, but on the other side of an interior wall. The second GFCI is located in the "mud room" and it occassionally trips when he sits down to remove his shoes. Weird things happen all the time.
 
102 Inspector said:
This a Motorola radio and he indicates that he is not transmitting when it trips the device. Normally he places his radio on the dresser and the GFCI in the adjacent bathroom actually trips. Approx. 18" away directly line, but on the other side of an interior wall. The second GFCI is located in the "mud room" and it occassionally trips when he sits down to remove his shoes. Weird things happen all the time.
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This is very interesting. Some questions....

Is he the only one at the station that has this issue, or are others experiencing the same thing?

If it is just him, could he change radios? It may be a defect in the radio that Motorola would be interested in knowing about.

As for the mud room, he may be accidentally pushing the PTT when he sits down. But the anomaly is when the radio is not even being touched it acts like it is transmitting.

If you can narrow the problem down to the radio, it may be intermittently transmitting dirty spurious signals as the result of an internal electronic failure of some sort. Also, if this is the only radio with the issue, the issue may be a precursor to a total failure down the road. That's an even better reason to get a different radio than the nuisance GFCI tripping.
 
102 Inspector said:
One of our firefighters has had issues with the portable radio tripping a GFCI receptacle when he is within 3 feet of the device. The radio is not even transmitting, just on. The radio is an 800 megahertz VHF radio. I have told him to place the radio near the kitchen circuit and see if it does it to all the circuits. Currently he says it impacts 2 circuits that he knows of. Is there any reason why this would be occuring? It does not happen all the time, very random. Thank you.
Click to expand...

There may be a serious problem in the radio of leakage of the local oscillator signal out the antenna or through the case. I would look into that, since it would be an FCC violation to use such equipment, especially if the oscillator frequency is in a band which is has critical users.

It sounds like the problem signal is getting into the GFCI via the attached wiring rather than direct radiation. If the GFCI is in a metal box and the trip happens from the far side of the wall, that makes it more likely. It would be interesting to try putting a metal faceplate over the GFCI to see what effect it has.
 
GoldDigger said:
There may be a serious problem in the radio of leakage of the local oscillator signal out the antenna or through the case. I would look into that, since it would be an FCC violation to use such equipment, especially if the oscillator frequency is in a band which is has critical users.

It sounds like the problem signal is getting into the GFCI via the attached wiring rather than direct radiation. If the GFCI is in a metal box and the trip happens from the far side of the wall, that makes it more likely. It would be interesting to try putting a metal faceplate over the GFCI to see what effect it has.
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Good observation. The common freqs. are 10.7 and 14.25 MHz. Both in the HF range. But I don't see how the oscillator can produce enough RFI to trip a GFCI, even if leaky. It would seem that something putting out that much power on receive would run the battery down real fast.

I do agree that if a leaky oscillator is bad enough to trip a GFCI, the radio has a serious problem.
 
102 Inspector said:
This a Motorola radio and he indicates that he is not transmitting when it trips the device. Normally he places his radio on the dresser and the GFCI in the adjacent bathroom actually trips. Approx. 18" away directly line, but on the other side of an interior wall. The second GFCI is located in the "mud room" and it occassionally trips when he sits down to remove his shoes. Weird things happen all the time.
Click to expand...

Is he 100% sure its the radio? Could he be leaning on the wall or pushing on something when he sits down that causes the GFCI to trip? Just for example, if there were a wire in the wall pinched by a staple, I could see it tripping the GFCI if he leans on the wall while sitting down.

If he is sure its the radio tripping the GFCI, I'd still try replacing the GFCI before I blamed the radio.
 
The problem issue is a his private home. The radios are multi channeled and scan continuously even if they are not transmitting. The outlets are in non-metallic boxes and I believe he said they were Leviton brand in a newly constructued home and I have suggested changing out the cover plates to metal covers. I guess the theory is that the cover plate disrupts the signal enough to not impact the device. He will change the plates and give me an update after a couple days. Again, this is the first I have ever heard about this. I have learned alot as always from the contributors at this site.
 
102 Inspector said:
The problem issue is a his private home. The radios are multi channeled and scan continuously even if they are not transmitting. The outlets are in non-metallic boxes and I believe he said they were Leviton brand in a newly constructued home and I have suggested changing out the cover plates to metal covers. I guess the theory is that the cover plate disrupts the signal enough to not impact the device. He will change the plates and give me an update after a couple days. Again, this is the first I have ever heard about this. I have learned alot as always from the contributors at this site.
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Are you sure this is an 800 meg radio? Usually they are trunked and are always set to recieve from the control frequency. 800 meg handhelds don't usually have a scan feature.

Is this a radio that belongs to the fire department? None of our FD's use radios that scan.

It's more common to have a VHF radio that scans. I went to see if I could detect my scanner with my hand held and lo and behold, someone or something is locking up our central dispatch frequency.

So, I think I will be making a phone call or two.....
 
Well, that was strange....

First call I made was to other side of county. CD freq was locked up there, so I knew it wasn't local. Second call was to cop in northern part of county. He also verified the problem and was going to call CD to let them know they weren't dropping out. A few seconds after I hung up from the cop, CD started working OK all on it's own. I guess that's good, but now we don't know what the problem was.....

But, my quickie experiment did not detect RFI from my scanner which scans real fast.
 
steve66 said:
Is he 100% sure its the radio? Could he be leaning on the wall or pushing on something when he sits down that causes the GFCI to trip? Just for example, if there were a wire in the wall pinched by a staple, I could see it tripping the GFCI if he leans on the wall while sitting down.

If he is sure its the radio tripping the GFCI, I'd still try replacing the GFCI before I blamed the radio.
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It's not a matter of blame. Besides the FCC thing mentioned, the radio is a firefighter's life line. If it has a problem of any kind, it should not be used. It should be taken out of service immediately, inspected and repaired or discarded.

That's why I suggested switching radios. That would be the first step in making 100 percent sure that it's the radio.
 
K8MHZ said:
It's not a matter of blame. Besides the FCC thing mentioned, the radio is a firefighter's life line. If it has a problem of any kind, it should not be used. It should be taken out of service immediately, inspected and repaired or discarded.

That's why I suggested switching radios. That would be the first step in making 100 percent sure that it's the radio.
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Maybe it's his personal electric field. :D

http://forums.mikeholt.com/showthread.php?t=152333
 
K8MHZ said:
Good observation. The common freqs. are 10.7 and 14.25 MHz. Both in the HF range.
I do agree that if a leaky oscillator is bad enough to trip a GFCI, the radio has a serious problem.
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Think again. If the IF frequency is 10.7 or 14.25, there may be a secondary local oscillator near that to bring the signal down to a 2nd IF frequency.
But if the RF frequency is 800MHz, the first LO will be that plus or minus 10.7.
There may be an incidental tuned circuit in the GFCI which is sensitive to one of those frequencies, since the output signal from the internal CT has to be amplified quite a bit to trigger the relay.
 
Some fire and police radios also transmit a locating burst every so many minutes, it could be tripping during one of these locating transmissions? they use this to locate a down officer or fireman.
 
102 Inspector said:
One of our firefighters has had issues with the portable radio tripping a GFCI receptacle when he is within 3 feet of the device. The radio is not even transmitting, just on. The radio is an 800 megahertz VHF radio. I have told him to place the radio near the kitchen circuit and see if it does it to all the circuits. Currently he says it impacts 2 circuits that he knows of. Is there any reason why this would be occuring? It does not happen all the time, very random. Thank you.
Click to expand...

About 25 years ago we started to be concerned about our intrinsically safe, limited power output two-way radios affecting out 4-20mA signals. Sure enough we demonstrated with the then most common transmitters, cover removed of a heavy XP aluminum enclosure, keying the radio within 3' would produce an erroneous signal that would/could shut down operations. With the cover in place one can put the radio on top of the transmitter and nothing would happen, regardless what the radio did. Certainly makes a GFI/GFCI without any RF shielding to malfunction not outside the realm of possibility.

There were also bold signs on some of our control rooms "no portable radios allowed" and they would have a desk station with a remote antenna outside of the room, but the operators were not allowed to bring their portables into the area. We were looking for the origin or empirical evidence form the base of such restriction, but I've never seen any produced. Nowadays I see operators sitting at the board with the handhelds in hand.
 
I am certainly suprised with all the responces that I have received regarding this issue. Sounds like this is not the only one out there that might be doing this. Our radios work at the 800 range and scan multiple ranges and channels. 16 channels each bank with 4 banks of channels. Motorola XTS 5000R to be exact. I am going to have him change out radios for a week and see if problem continues. I am also going out to his house today with my radio to see if same issue can be duplicated. Because my after work hobby is to serve as Assistant Fire Chief, the radio being the problem does have me concerned so thanks for pointing out those issues. I will try to update after trying some of these suggestions.
 
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