How to avoid shock hazard with aquarium heater ???

[jalbers@bsu.edu]

I use a store bought 50 watt aquarium heater to warm water in a 5
gallon bucket in my cold garage. I use the bucket of water to pre-wash
my greasy hands before finally washing in the kitchen sink. The heater
is basically a sealled test tube with resistance wire wrapped around a
piece of ceramic inside of the test tube. The heater is plugged into a
regular wall outlet.

I was wondering what would happen if I didn't know that the glass test
tube was cracked and I stuck my hands down into the water?

Would installing a GFCI on the outlet that the heater is plugged into
be enough protection?

What about placing a bare copper wire connected to ground inside of the
bucket. Would this help trip the GFCI the instant that the glass
cracked?

Any help would be greatly appreciated. Thank You

 

[Chris]

John Popelish wrote:

If you ground the bucket (sit it in a bit of metal that is connected
to a water pipe) and plug the heater into a GFCI, it should trip the
moment any connection is made between the line and the water.

--
John Popelish

Mr. Popelish is correct. Also, you might want to add some kind of
baffle over the heater tube. Touching the glass can break it due to
the thermal stress. Try to keep the baffle from touching the glass,
too.
You might want to ground the baffle to help with both problems.

Chris

 

[David Harmon]

On Mon, 31 Jan 2005 10:44:53 -0500 in sci.electronics.basics, John
Popelish <jpopelish@rica.net> wrote,

If you ground the bucket (sit it in a bit of metal that is connected
to a water pipe) and plug the heater into a GFCI, it should trip the
moment any connection is made between the line and the water.

I am guessing that the bucket is too good of an insulator for that to
work reliably.

 

[John Popelish]

"jalbers@bsu.edu" wrote:

I use a store bought 50 watt aquarium heater to warm water in a 5
gallon bucket in my cold garage. I use the bucket of water to pre-wash
my greasy hands before finally washing in the kitchen sink. The heater
is basically a sealled test tube with resistance wire wrapped around a
piece of ceramic inside of the test tube. The heater is plugged into a
regular wall outlet.

I was wondering what would happen if I didn't know that the glass test
tube was cracked and I stuck my hands down into the water?

Would installing a GFCI on the outlet that the heater is plugged into
be enough protection?

What about placing a bare copper wire connected to ground inside of the
bucket. Would this help trip the GFCI the instant that the glass
cracked?

Any help would be greatly appreciated. Thank You

If you ground the bucket (sit it in a bit of metal that is connected
to a water pipe) and plug the heater into a GFCI, it should trip the
moment any connection is made between the line and the water.

--
John Popelish

 

[Chris]

Chris wrote:

John Popelish wrote:
If you ground the bucket (sit it in a bit of metal that is
connected
to a water pipe) and plug the heater into a GFCI, it should trip
the
moment any connection is made between the line and the water.

--
John Popelish

Mr. Popelish is correct. Also, you might want to add some kind of
baffle over the heater tube. Touching the glass can break it due to
the thermal stress. Try to keep the baffle from touching the glass,
too.
You might want to ground the baffle to help with both problems.

Chris

I guess it might also be worthwhile mentioning that the way people
usually do something like this safely is to use a small hotplate.

The concept of directly relying on a GFCI for safety in an application
where you could have a catastrophic fault under normal use doesn't
appeal to me. They're designed as a last line of protection in the
event of an accident. The people who make GFCIs would tell you that
you're misapplying it.

Good luck
Chris

 

[w_tom]

GFCI is secondary protection. A GFCI could be damaged by,
for example, transients. Then GFCI would only appear to
provide protection up to and not including when protection was
required. Press that GFCI test button before washing hands.

Ground wire to water pipe has a major flaw. Metal water
pipes are sometimes patched with plastic. IOW was that water
pipe was a good ground? Do you want to learn after the fact?

GFCI needs a 'whole house' protector installed on AC mains
in the breaker box. Water pipe as a ground need be confirmed
by a large current test or by visual inspection. Pipe must
make a complete electrical connection back to break box. Best
make a habit of pressing that GFCI test switch.

"jalbers@bsu.edu" wrote:

I use a store bought 50 watt aquarium heater to warm water in a 5
gallon bucket in my cold garage. I use the bucket of water to pre-wash
my greasy hands before finally washing in the kitchen sink. The heater
is basically a sealled test tube with resistance wire wrapped around a
piece of ceramic inside of the test tube. The heater is plugged into a
regular wall outlet.

I was wondering what would happen if I didn't know that the glass test
tube was cracked and I stuck my hands down into the water?

Would installing a GFCI on the outlet that the heater is plugged into
be enough protection?

What about placing a bare copper wire connected to ground inside of the
bucket. Would this help trip the GFCI the instant that the glass
cracked?

Any help would be greatly appreciated. Thank You

 

[Jim Douglas]

Cut up some PVC pipe larger than then glass to protect it, it's bigger and
not touching the glass.

<jalbers@bsu.edu> wrote in message
news:1107179271.806710.183510@c13g2000cwb.googlegroups.com...

I use a store bought 50 watt aquarium heater to warm water in a 5
gallon bucket in my cold garage. I use the bucket of water to pre-wash
my greasy hands before finally washing in the kitchen sink. The heater
is basically a sealled test tube with resistance wire wrapped around a
piece of ceramic inside of the test tube. The heater is plugged into a
regular wall outlet.

I was wondering what would happen if I didn't know that the glass test
tube was cracked and I stuck my hands down into the water?

Would installing a GFCI on the outlet that the heater is plugged into
be enough protection?

What about placing a bare copper wire connected to ground inside of the
bucket. Would this help trip the GFCI the instant that the glass
cracked?

Any help would be greatly appreciated. Thank You