GFCI and ballasts

[SantaMonica]

Question for the power experts:

1. If I'm powering a fluorescent bulb with a Fulham Workhorse 2 (or similar) ballast, will the ballast function as it's own GFCI if the leads of the bulb are touched by somebody with wet hands? (The Workhorse 2 has a "built in circuit breaker").

2. If I use a GFCI before the ballast, will the GFCI still be able to detect faults at the bulb, since the GFCI must now do it "sensing" through the ballast?

Thanks

 

[Reloadron]

Question for the power experts:

1. If I'm powering a fluorescent bulb with a Fulham Workhorse 2 (or similar) ballast, will the ballast function as it's own GFCI if the leads of the bulb are touched by somebody with wet hands? (The Workhorse 2 has a "built in circuit breaker").

2. If I use a GFCI before the ballast, will the GFCI still be able to detect faults at the bulb, since the GFCI must now do it "sensing" through the ballast?

Thanks

1. No
2. No

The ballast from what I read has built in overload protection not GFIC protection. There is a big difference here.

A GFIC looks at the current entering a circuit on the "hot" side and compares it to the current leaving a circuit on the "neutral" side. They should be the same. If the GFIC detects more current on the goes in than goes out it assumes the missing current is going somewhere where it shouldn't and trips. That being simply put.

A circuit breaker simply trips when current through the circuit exceeds a limit much higher than the limits that cause death or bad things to happen. Circuit breakers are not designed for shock hazard safety.

Actually as to #2 I am not 100% but I doubt after going through a ballast transformer a GFIC would detect a ground fault? I guessed No.

Ron

 

[MikeMl]

The GFCI reacts to current flow inbalance between the Black wire (Line) and the White wire (Neutral). Any leakage to earth ground (through a person, for example) causes it to trip. If the ballast incorporates an isolated winding (primary to secondary), then that provides protection from getting shocked, and it matters not if the GFCI trips. If the ballast is just an autotransformer (no isolation), then the GFCI would trip normally.

 

[SantaMonica]

Any idea if electronic ballasts count as osha GFCI protection?

 

[Reloadron]

Any idea if electronic ballasts count as osha GFCI protection?

No, they don't. A ballast, even a ballast with a shutdown (overload) feature is not a GFCI. The NEC in the US is pretty specific as to what a circuit breaker, GFCI and AFCI are.

Ron

 

[SantaMonica]

The Fulham is "protected", but I don't know if the outputs are isolated from the inputs. The question is, if the outputs (the bulb) are dropped in or spashed with water, will the person holding the bulb be shocked.

Or a better question is, would you know if the ballast's inputs are electrically isolated from the outputs?

 

[Reloadron]

The Fulham is "protected", but I don't know if the outputs are isolated from the inputs. The question is, if the outputs (the bulb) are dropped in or spashed with water, will the person holding the bulb be shocked.

Or a better question is, would you know if the ballast's inputs are electrically isolated from the outputs?

Without seeing this configuration I can't begin to say. Generally a fluorescent ballast is configured in a way that it is not line isolated. My simple advice would be to have anything like that around water that a person comes in contact with on a GFCI. The idea being in any industrial or work environment to make people as safe as possible from injury or death as a result of electrical shock.

Ron

 

[SantaMonica]

If the ballast were isolated though, there would be no way for a fault to occur from the ballast output to ground, right?

 

[Reloadron]

That would be my guess. I am just not 100% and don't want to mislead you.

Ron

 

[3v0]

My thinking is.

A transformer primary is the load seen by the GFI.

A GFI can not sense any problems on the secondary side.

To get GFI protection on the output of a transformer you need to put the GFI on output side of a transformer.

My thinking starts to get fuzzy when a common ground connects the circuit on both side of the transformer. I am thinking that it does not matter because the GFI monitors hot and neutral current but ignores the GND.