Is There Anything to Report Here?

This is the exterior heat pump box. They ran a 4 wire feed to the box and combined the neutral and grounds. This is of course a no-no, but the load is 240 volts with no neutral. It seems like the neutral wire, which is not necessary, should dead end at a wire nut. But as there is no neutral current, I suppose it does not matter if the neutral wire is terminated at the ground bus. Does anyone read this differently? Is there any reason to call this out?

You are definitely correct about the bonded neutral and capping it off. I don’t like that it is terminated.

Also, I see no connector at the back of the enclosure.

The right hand fuse is upside down as well and may have damaged the top fuse clip and fuse reject device.

Looks like everyone covered what could be distinguished from this photo. I would point out that if the lid opens easily and exposes those components, that a comment be made about securing the lid. A small lock, a loop of wire tie, etc, to protect curious children.


Since there is no neutral current present I don’t see any real electrical problem. I suppose he could have reidentified the wire green to be perfectly legal. Then it would be “hospital safe”. :wink:

The wire could use a proper connector where it comes through the back of the box.

Conductors of that small of a gauge are not permitted to be paralleled. Even though you have no neutral current, what you effectively have there is a parallel equipment grounding path. The equipment ground is also not permitted to be white… it must be green or bare. That white wire should be capped off to comply with the code, but I’d be hard pressed to tell you that any special hazard is created by letting it remain as-is.

You can parallel grounding paths Marc, we do it all the time (conduit with a green wire). In fact it is required in patient care areas, hence my reference.
We also reidentify grounding conductors in IG circuits all the time.
If you really wanted to be pedantic and never be able to go back, you could strip it.

Thanks for the comments all. The upside down fuse is a new one to me. I didn’t realize you could put a fuse in the wrong way. I see the groove at one end of the fuses. I will look for that in the future.

For those interested, the following explains reh=hection type fuses:

Class R Fuses
Class R (“R” for rejection) fuses are high performance, ⁄Ω¡º to 600
ampere units, 250V and 600V, having a high degree of current-limitation
and a short-circuit interrupting rating of up to 300,000
amperes (RMS symmetrical). BUSS® Class R’s include Classes
FUSETRON® fuses. They have replaced BUSS® K1 LOW-PEAK®
and LIMITRON fuses and K5 FUSETRON® fuses. These fuses are
identical, with the exception of a modification in the mounting configuration
called a “rejection feature”. This feature permits Class R
to be mounted in rejection type fuseclips. “R” type fuseclips prevent
older type Class H, ONE-TIME and RENEWABLE fuses from
being installed. Since Class H fuses are not current-limiting and
are recognized by regulatory agencies as having only a 10,000
ampere interrupting rating, serious damage could result if a Class
R fuse were replaced by a Class H fuse. The use of Class R fuseholders
is thus an important safeguard. The application of Class R
fuses in such equipment as disconnect switches permits the
equipment to have a high short-circuit current rating. NEC® 110.9
requires that protective devices have adequate capacity to interrupt
short-circuit currents. NEC® 240.60(B) requires fuseholders for current-
limiting fuses to reject non-current-limiting type fuses.
In the above illustration, the fuse on the right has a grooved
ring in one ferrule, providing the rejection feature of the Class R
fuse in contrast to the lower interrupting rating, non-rejection type.


More Fuse Info(PDF)