Hammond Organ dilema

[Robert Wikstrom]

Ok Ok Ok....so here comes the old guy that still hauls around a Hammond B3 with Leslie 122. My B3 has never failed me until recently when we were hired to play at a couple of outdoor events in the park. The only outlets we had were GFI outlets. As soon as I plugged in the Hammond, even before turning it on, the GFI was tripped. I know it was the Hammond because I unplugged everything else except my rig. Even tried different extension cords. No luck. Anyone have a clue?

 

[Gourockian]

It seems rather strange that the mere act of just plugging in the B3 tripped the GFI, before you turned it on. However, it's possible that the mains cord has been damaged and possibly is shorted. Try checking across the pins with a meter set to resistance or continuity, with the B3 turned off. It should indicate if you have a short.

Have you been able to power it up okay elsewhere, since that happened. If so, I suspect it has something to do with the venue's power supply.

 

[delaware dave]

A hammond plug has no grounding pin, this may have caused the issue. If you have a gfi outlet at home (you should have one near a bathroom where there are water sources) try plugging the hammond into it with the same cord you used outside and see if it trips the gfi at your house. It probably will.

 

[Robert Wikstrom]

It seems rather strange that the mere act of just plugging in the B3 tripped the GFI, before you turned it on. However, it's possible that the mains cord has been damaged and possibly is shorted. Try checking across the pins with a meter set to resistance or continuity, with the B3 turned off. It should indicate if you have a short.

Have you been able to power it up okay elsewhere, since that happened. If so, I suspect it has something to do with the venue's power supply.

Thanks. Played it the next night in a club. No problems. Tried several different cords, all with the same result. Am thinking it has to be the venue. However, this was two different venues. One was a park the other a club where we played outdoors. Both had GFIs. In no other venue we play are we forced to plug into a GFI circuit.

 

[Robert Wikstrom]

A hammond plug has no grounding pin, this may have caused the issue. If you have a gfi outlet at home (you should have one near a bathroom where there are water sources) try plugging the hammond into it with the same plug you used outside and see if it trips the gfi at your house. It probably will.

You may be on to something although my Hammond does have a grounding pin. It's a Bill Beers Chopper" that was modified many years ago. Perhaps that ground pin is actually nothing.

 

[Gourockian]

May be worth investing in a decent power conditioner, if you don't already have one.. It might not have helped in this case but at least your gear will be better protected in future.

 

[seanL122]

Hammond transformers are famous for being "leaky" when they get old. Sometimes when the organ has been modified to add the three-prong plug, there will be leakage current that flows from chassis to ground terminal on the plug. If the leakage current is "too high" there is the risk of damaging the transformer, or the humans that touch it.

AFAIK, the recommended "solution" is to buy a new transformer, but this is unbelievably expensive, so nobody does it.

If your organ trips a GFI outlet with the three-prong plug, try a ground-lift plug into that outlet, and there will be no way to trip the GFI.

Search for "Hammond Transformer Leakage" meaning electrical current leakage, not PCB leakage.

Some info about the Hammond AC leakage test - The Organ Forum

This is the place to discuss the Hammond organ models and their technical aspects.

organforum.com

 

[Old No7]

Ok Ok Ok....so here comes the old guy that still hauls around a Hammond B3 with Leslie 122.

Man -- you've got some b*lls, for sure -- good for you! -- and maybe a strong back and a couple of willing helpers too! Back in the early 80's, I used to lug around a smaller chop -- an M3 & a Leslie 147 -- and nowadays, I don't at all mind carrying my Hammond SK Pro 73.

Old No7

 

[oasislv]

Ok Ok Ok....so here comes the old guy that still hauls around a Hammond B3 with Leslie 122. My B3 has never failed me until recently when we were hired to play at a couple of outdoor events in the park. The only outlets we had were GFI outlets. As soon as I plugged in the Hammond, even before turning it on, the GFI was tripped. I know it was the Hammond because I unplugged everything else except my rig. Even tried different extension cords. No luck. Anyone have a clue?

let's not rule out the GFI itself. That plug could have failed. Liked your approach to troubleshooting!

 

[hotraman]

I used to own an A 101. Loved it, but never gigged with it.
Love that Hammond B3 sound. My Kurzweil PC4 88 has some nice Hammond setting, where you get to move the " sliders". But nothing beats a live Hammond organ with a Leslie.

 

[Old No7]

But nothing beats a live Hammond organ with a Leslie.

True enough, but at only 25 pounds (plus a 15-pound hard case), my Hammond SK Pro 73 comes so close that 99% of the audience can't tell the difference.

But my back sure can!!!

Old No7

 

[BleugrassBoy]

99% of the audience can't tell the difference.

This is Truth

 

[Old Master Tech]

Ok Ok Ok....so here comes the old guy that still hauls around a Hammond B3 with Leslie 122. My B3 has never failed me until recently when we were hired to play at a couple of outdoor events in the park. The only outlets we had were GFI outlets. As soon as I plugged in the Hammond, even before turning it on, the GFI was tripped. I know it was the Hammond because I unplugged everything else except my rig. Even tried different extension cords. No luck. Anyone have a clue?

After verifying the rig is safe...To treat the symptom, get an isolation transformer. If the Leslie gets power via a 6-pin connector, you'll need a fairly large one of about 500 watts. If not, then 200 watts should work fine.