Would you add a ground probe to a tank that didn't use a GFCI? I know I would not as that would be like taping a ground to your leg and then touching electrical machinery. If you had a short in your lights and your hands in the water, touching the lights with your head could kill you. Electricians who work with live loads avoid grounds, so they don't subject themselves to current flow.
Now you have grounded your tank and the only thing protecting you is a safety device called a GFCI. They don't always work by the way, leaving you with a grounded tank.
I agree that is a far more complicated situation. I'd never run a tank without a GFCI, but if you do not have one, a ground probe may be a safety hazard. For example, if you touched a light fixture that was live with 120 v, and then touched the water that was grounded at the same time.
The analogy is the grounding of kitchen appliances. It is not always safer to ground them if a second nearby appliance (like a kitchen blender) might provide a path to ground if you touched it when live from the first malfunctioning appliance.
IMO, GFCI are absolutely essential. Then a secondary consideration is a grounding probe, which is desirable, IMO.
GFCI's measure the outgoing current and compare it to the returning current. If there is a difference, there must be a short, so the unit trips. There is no need for a ground. I have installed them in older homes with out grounds. They work fine. Please be accurate as you have a reputation in chemistry and others will believe what you say here too.
Absolutely true, and it doe snot disagree with what I said. But if tanks are ungrounded, there may be no path to ground from a broken device, and so may not trip until you provide that path with your body.
I also agree that GFCI's alone do not completely protect. I had wet salty hands once and grabbed a plug when I shouldn't have. Current came out the hot and down the neutral, never tripping the GFCI since none leaked to ground, but sending a jolt through my fingers.
Now you have grounded your tank and the only thing protecting you is a safety device called a GFCI. They don't always work by the way, leaving you with a grounded tank.
I agree that is a far more complicated situation. I'd never run a tank without a GFCI, but if you do not have one, a ground probe may be a safety hazard. For example, if you touched a light fixture that was live with 120 v, and then touched the water that was grounded at the same time.
The analogy is the grounding of kitchen appliances. It is not always safer to ground them if a second nearby appliance (like a kitchen blender) might provide a path to ground if you touched it when live from the first malfunctioning appliance.
IMO, GFCI are absolutely essential. Then a secondary consideration is a grounding probe, which is desirable, IMO.
GFCI's measure the outgoing current and compare it to the returning current. If there is a difference, there must be a short, so the unit trips. There is no need for a ground. I have installed them in older homes with out grounds. They work fine. Please be accurate as you have a reputation in chemistry and others will believe what you say here too.
Absolutely true, and it doe snot disagree with what I said. But if tanks are ungrounded, there may be no path to ground from a broken device, and so may not trip until you provide that path with your body.
I also agree that GFCI's alone do not completely protect. I had wet salty hands once and grabbed a plug when I shouldn't have. Current came out the hot and down the neutral, never tripping the GFCI since none leaked to ground, but sending a jolt through my fingers.
