Good ways to close the output power cable on a condensate pump?

[Adam Funk]

I've just received a Grundfos condensate pump to use under the basement dehumidifier.

The old pump (which seized up after about 6 years) had a sealed-up cable that you could strip and use optionally to power something else (with a cut-off if the tank gets full and fails to empty). But you didn't have to do anything if you weren't going to use that cable.

The new one came with bare wires on both the incoming (no plug!) and outgoing cables. As a temporary measure, I stuck Wago blocks on the wires and a Wago box on the cable. What are some good ways to cap the cable off? I was thinking of heat-shrink insulation on each wire, then a piece shrunk onto the end of the cable with some excess to fold over and then cover with another layer.

Thanks.

[Adrian Caspersz]

Isn't there a terminal box on the pump, accessible if you remove a cover? Then you can cable it with whatever.

Sometimes installation things are supplied with short lengths of wire as they get tested with them on the final stage of the production line?

[John Rumm]

These things are normally "wired in" so no need for a plug in many applications. (or at least that is enough plausible deniability to save the maker forking out to fit one at all, let alone the right one for the target market)

Take both cables into an enclosure of some kind using approprote strain relief glands. Then wire up the wires you need using whatever jointing method you fancy, and terminate unused wires in a terminal of some kind (chock block, wago, insulated butt crimp etc - basically something that stops the conductive bit coming into something it should not, and won't fall off.

No need to be too anal about insulation since they are all enclosed in a box that needs a tool to access, and protected from being pulled out of the box by the entry gland.

[Adam Funk]

Yes, the leaflet says "The power supply cable has a Schuko plug or a free cable end. The cable has a length of 2 metres."

Oh, I've already put a 13 A plug on the input cable and started using it!

OK, I was just looking for a non-bulky way to terminate the output cable so I can coil it up and cable-tie it out of the way!

[Adam Funk]

It's definitely meant to be used for powering something else --- see section 3.2.1 of the manual:

but that does make it sound like it's OK to open the thing up and change the connections, so I suppose I could open it up and remove the output cable entirely.

[John Rumm]

Either a small dedicated box or similar then, or some adhesive lined heat shrink.

If you cut the individual wires such that they are slightly staggered. Get a couple of bits of heatshrink, shrink the first in place such that it overhangs the end of the cable. Then fold over the free end and stick another bit over it and the cable to hold it against the side of the cable in the folded position. That should fix it all in place, and not leave any possibility of accidentally poking something conductive up the open end of the heatshrink. The adhesive will stop it being accidentally being pulled off.

[Adrian Caspersz]

Strange manual, no mention on what colour the rest of the wires are, and a view of the terminal block would be in place to identify what goes where when the day comes for head scratching.

The alarm output wires look to me connected just to relay contacts, they are not energised internally (unless the manual is telling fibs)

[Adam Funk]

Huh, I didn't even think of that! I just saw an extra cable coming out with blue and brown wires and assumed. The old one (different brand) definitey had an output power cable with a separate float switch to cut it off.

[ARW]

A pro would just use insulation tape.....

[Adam Funk]

You're absolutely right. I checked it (with a volt stick, then a voltmeter, then an ohmmeter [1]). Normally the two wires are connected; when I unplugged the pump and filled the tank up (quite full) they became disconnected; then I plugged the pump in and they were reconnected not long after.

[1] The same meter, on different settings.

[Adam Funk]

Adrian was right --- the wires are not powered. They're just connected internally unless the tank is really full (the blue and brown insulation was a red herring). So I've just taped them up for aesthetics and coiled that lead up beside the pump.