# Selection of multi-pin connector for power lead cables

Hi,
I have 6 cables. Each cable has 3 wires: zero, phase, earth.
Each cable supplies 320W 230VAC heater (I have 6 heaters).

I am looking for 1 multi pin connector for all these cables for quick plug in/out.
https://www.aliexpress.com/cheap/cheap-multi-pin-connectors.html

I wonder how many pins my connector must have. I have 18 wires in 6 cables (6xZero, 6xPhase, 6xEarth).
Does it mean that I need at least 18 pin connector or can I have the earth wires connected together?

Also I have calculated that each heater draws approx. 1.4A (320W, 230VAC). Therefore, when I multiply 1.4A by 6 heaters my amperage is 8.4A. Sellers state the amperage for the multi pin connector. I understand that this is maximum load that the connector can take?
In my case should I then look for minimum 10A connector?

Regards

berkeman
Mentor
Hi,
I have 6 cables. Each cable has 3 wires: zero, phase, earth.
Each cable supplies 320W 230VAC heater (I have 6 heaters).

I am looking for 1 multi pin connector for all these cables for quick plug in/out.
https://www.aliexpress.com/cheap/cheap-multi-pin-connectors.html

I wonder how many pins my connector must have. I have 18 wires in 6 cables (6xZero, 6xPhase, 6xEarth).
Does it mean that I need at least 18 pin connector or can I have the earth wires connected together?

Also I have calculated that each heater draws approx. 1.4A (320W, 230VAC). Therefore, when I multiply 1.4A by 6 heaters my amperage is 8.4A. Sellers state the amperage for the multi pin connector. I understand that this is maximum load that the connector can take?
In my case should I then look for minimum 10A connector?

Regards
What country are you in? In the US, you would need to consult the NEC (National Electric Code) standard to figure out what the spacings should be between the pins in the connectors, and what size wire you need to use.

How long are the cable runs? Is this in a factory? What building inspections and insurance inspections will be involved in getting this new electrical installation approved?

Tom.G
One thing to watch out for is Tin plated or solder coated contacts. For some reason, perhaps oxidation, many such contacts have or develop a high resistance connection. This results in poor electrical contact, higher temperature, rapid oxidation/corrosion of the contacts, and failure. If you must use Tin or solder contacts use at least a 60% current derating. Even if this is in an office or home environment or similiar, do not use Tin or solder contacts for any significant current, they fail.

CWatters
Homework Helper
Gold Member
It's a rather badly specified problem. As far as I can see you may only need three pins on the connector (Phase, Neutral & Earth) and perhaps some junction box(es).

Some C13 IEC connectors (aka Kettle leads) will handle 15A.

However that could be totally inappropriate depending on other factors.

Do you want to be able to disconnect the connector with the power ON?
Are all the phases the same phase?
How frequently will it be connected disconnected?

Is each of the six heaters individually controlled as one of your previous questions suggests they may be?

Several approaches exist each with their own set of pros and cons.

rbelli1
Gold Member
Do you want to be able to disconnect the connector with the power ON?

I would suggest avoiding this situation if possible even for live power rated connectors. Even though many mains connectors are often used for connect and disconnect under load it is not an optimal situation. It is just a potentially dangerous historical foible.

BoB

CWatters
@berkeman
I live in the EU.
Each cable is 5meters long.
This is the factory (production).
Electrician with appropriate certificates is authorised to approve the installation.

@CWatters/Asymptotic
Each heater is controlled individually by the PLC (through feedback from its TCK). Therefore, each heater requires separate wires.
There is no need to disconnect the plug with power ON.
All phases are the same (230VAC).
The disconnection will take place once a week.

CWatters
Homework Helper
Gold Member
If you are stuck with the 6 separate cables I think it will be difficult to find an 18 pin connector pair to do this job reliably. Mainly because the strain relief on the majority of connectors is intended for one 18 way cable not six 3 way cables. You would probably need to strip the cables and reassemble the 18 individual wires into one 18 way cable using heat shrink sleeving. To do a neat job would require the cables to be disconnected at the heater end to slip the heat shrink over the bundle. Possible but not ideal.

Do both halves of the connector have to be "in-line" or can one be panel mounted? In some connector ranges you can only connect a cable mounted connector to a panel mounted connector, You can't connect cable mounted to cable mounted. If you can disconnect at a panel then that might give you more options.

If you can rewire then speak to the electrician about the number of wires/cores he thinks are needed. I guess it could be as few as 8?...

6 phase
1 Neutral (10A)
1 Earth

In which case perhaps look at the Bulgin Buccaneer Series of connectors which go up to 10 way. I think they have cable to cable versions but I haven't checked.

http://uk.rs-online.com/web/p/industrial-automation-circular-connectors/0575715/
http://docs-europe.electrocomponents.com/webdocs/0c63/0900766b80c63e01.pdf

These are plastic connectors so not really suited to places where they might get stepped on/driven over although they are pretty robust. Metal connectors will be quite a bit more expensive.

Your electrician should really be sorting this for you.

@berkeman
I live in the EU.
Each cable is 5meters long.
This is the factory (production).
Electrician with appropriate certificates is authorised to approve the installation.

@CWatters/Asymptotic
Each heater is controlled individually by the PLC (through feedback from its TCK). Therefore, each heater requires separate wires.
There is no need to disconnect the plug with power ON.
All phases are the same (230VAC).
The disconnection will take place once a week.

I've used this type of connector in similar applications with good results.

They are available through several different manufacturers. Here is the AutomationDirect catalog page because they've done a good job at simplifying the selection of which parts go with what, but the ones I used were mostly by Thomas & Betts, and a German company whose name escapes me at the moment.

To use this option:
1. Mount an appropriately sized steel enclosure to the device the heaters are used in, and route the six heater cables into it.
2. Mount a grounding bar in the enclosure. Terminate the the heater ground wires to it, and run a wire from it to the ground tab of the plug.
3. Mount the connector body (the part with the swing arm clamp) onto the enclosure. Use the male connector block in this body. and wire the heater power wires to it.
4. Wire the plug body and female connector block to the heater power controllers.

Also I have calculated that each heater draws approx. 1.4A (320W, 230VAC). Therefore, when I multiply 1.4A by 6 heaters my amperage is 8.4A. Sellers state the amperage for the multi pin connector. I understand that this is maximum load that the connector can take?
In my case should I then look for minimum 10A connector?

The question is, "how much current runs through each pin"?
6 heaters, 12 pins, 1.4A per pin. (assuming 230V line-to-line).

10A will certainly do. However, another consideration is whether you plan on using them elsewhere. The cost difference between 10A and 16A isn't much, and 16A gives the flexibility to use the same connector over a wider range of projects while eliminating the need to maintain both 10A and 16A parts in emergency stock.

Thank you All for the answers.
@Asymptotic
This is exactly the same multi pin connector which I would like to use.
Also, the solution you had suggested is the same scenario as I planned.
Indeed, there is no harm to use pins rated for 16A.
As soon as I have the pricings from the potential suppliers I will talk with the electrician.
Thank you for your clarifications in regards to the pins number and the grounding solution.
I am grateful.