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[keatingson]

Hi,

I am installing an additional submersible3 phase 415v pump for a fountain at my home in France

The original set up is as follows:

The existing cable (about 30 years old) has a plug at one end at the other (about 50m away)the cable terminates in a junction box. The existing pump is about 2 metres away from the junction box.

I have installed an additional pump (3 phase 415v) about 50m further on from the junction box (new cable). The jointing of the cables was done using jointing clips.

For about a month all worked well, then both pumps stopped working. We disconnected the plug from the socket and then inspected the junction box only to find that the cables had burnt out. I don’t know what caused the burn out.

I am thinking about replacing the junction box with a more robust box and installing a trip switch. I don’t know if I should also be replacing the existing cable?

I am assisted by a reasonably competent DIY guy, not an electrician.

Advice please as to what caused the burn out and what junction box/cable jointing I should use and if I should replace the existing cable.

Many thanks in anticipation....

[ericmark]

There are two reasons why cables will burn out.
1) Too small
2) Lose connection
I would guess the latter is the problem. Does not really matter is single phase, split phase or three phase joints do need making properly and using cheap motor DIY crimp pliers can cause problems. There are a number of way to join cables but most common outside would be in a epoxy resin filled joint with non insulated crimps. My guess is the joint you used was either not fitted correctly or was faulty.

[BLAKEY1963]

[quote="keatingson"]Hi,

I am installing an additional submersible3 phase 415v pump for a fountain at my home in France

The original set up is as follows:

The existing cable (about 30 years old) has a plug at one end at the other (about 50m away)the cable terminates in a junction box. The existing pump is about 2 metres away from the junction box.

I have installed an additional pump (3 phase 415v) about 50m further on from the junction box (new cable). The jointing of the cables was done using jointing clips.

For about a month all worked well, then both pumps stopped working. We disconnected the plug from the socket and then inspected the junction box only to find that the cables had burnt out. I don’t know what caused the burn out.

I am thinking about replacing the junction box with a more robust box and installing a trip switch. I don’t know if I should also be replacing the existing cable?

I am assisted by a reasonably competent DIY guy, not an electrician.

Advice please as to what caused the burn out and what junction box/cable jointing I should use and if I should replace the existing cable.

Many thanks in anticipation....[/quote]


KEATINGSON.
Good advice from ericmark.
Might be wise to seek advice from a local electrician , to disscuss installation methods out there in france.

BLAKEY1963

[keatingson]

I am most grateful for the advice thank you.

Keatingson