Quick Disconnects for motor power and signal cords

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charlie b

charlie b

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We are replacing a group of sump pumps that remove water from a drainage sump at a dam. Each pump can be hauled up (about 25 feet) by a chain connected to a bail. The power cord and signal cable are loosely attached to the chain, so they ride up when the motor is lifted. The current practice of the maintenance crew is to cut the cables and splice the new cables that come with the replacement pump. I would like to know if I can simplify this task by calling upon the motor manufacturer to include some type of quick disconnect for the power cord and the signal cord.

One of the replacement pumps is 100 HP and will have a three phase 2/0 power cord. Another pump is 40 HP and will have a three phase #4 power cord. Each pump will have temperature and vibration sensors. I am anticipating a 6 or 8 conductor #14 signal cable. Are there quick disconnects that can work with these cords?
 
480 volts. Not submersed, but the site wants all electrical components rated for a wet environment.
 
For the pump connectors I would suggest using ones that are IEC 309 type. The connectors are standardized for voltage and phase, and get this, interchangeable between manufacturers. Likely need to be field installed
For the signal cable there are small pin connectors I used a type from Brad Harrison called Micro Change, and they are a standard in Europe. Lots of choices number of pins etc. They would have to be field installed.
The other option is a NEMA junction box, wire basket grips and terminals, to disconnect and reconnect motor and signal leads
 
Pin-and-sleeve connectors of the appropriate rating for the voltage and current involved, and the connectors linked to below for signals.


The backshells are suitable for use in wet environments, and if you pick the correct inserts, they have screw terminations. I strongly advise the use of ferrules on the wires put in these connectors, based on some unfortunate personal experiences where field techs omitted the ferrules.



SceneryDriver
 
I've worked with all of these except Meltric. I was impressed with the presentation from mfg rep but they're $$$$
Meltric, TJB, amphenol, appleton, scame for pump.
Deutsch, amphenol for signal.


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You won’t get them from manufacturers that way but you can install your own. I’ve tried it both ways. It doesn’t save a tremendous amount of time.

Going the other way with shore power and mining systems I’ve found two good solutions. The first is just put some sort of gland system on a box. Run the whole cable in the box. Strip and crimp on lugs. Install lugs on studs with an impact gun. It takes only a couple minutes especially if the lugs are already installed and it’s very universal. We did this in a mine. The glands were home made. We just cut glastic with a notch for the cable. The seal wasn’t perfect but we had drain holes in the bottom of the box. This works fine and I’d used all over the US for up to 25 kV. I’m sure it will be fine on 480 V. It might seem to be crude but nothing else comes close in simplicity and reliability.

Second option is use crimp barrel connectors. On the signal wires use the adhesive lined waterproof ones. On bigger cables if it’s SO first slide one big heavy wall adhesive lined shrink tube over the cable. Then strip jacket and cut each wire offset. Slide individual shrink tubes over each wire. Strip and crimp on barrel connectors. Then shrink the tubing with a heat gun or propane or MAP gas burner. It sounds like a lot but I can do a 480 V connection in about 15 minutes from start to finish while working out of a boat on a pipeline shore power system for a dredge and it won’t fail if it goes underwater

The trouble with plugs is they always have failure issues and it takes longer to install. Granted you can install everything on scheduled time but then there is the trade off of the extra expense, extra labor, and lower reliability. I’d rather focus efforts on eliminating failures first thing then speed up changing only if I can’t fix the reliability. The above solutions are so quick it’s hard to justify plugs. Especially when you can unbolt and remove the pump “pigtail” if it’s bolted in. Both can be prepped ahead of time.
 
charlie b said:
We are replacing a group of sump pumps that remove water from a drainage sump at a dam. Each pump can be hauled up (about 25 feet) by a chain connected to a bail. The power cord and signal cable are loosely attached to the chain, so they ride up when the motor is lifted. The current practice of the maintenance crew is to cut the cables and splice the new cables that come with the replacement pump. I would like to know if I can simplify this task by calling upon the motor manufacturer to include some type of quick disconnect for the power cord and the signal cord.

One of the replacement pumps is 100 HP and will have a three phase 2/0 power cord. Another pump is 40 HP and will have a three phase #4 power cord. Each pump will have temperature and vibration sensors. I am anticipating a 6 or 8 conductor #14 signal cable. Are there quick disconnects that can work with these cords?
Click to expand...
We have used automotive parts. High current DC quick connects that connect on batteries. For charging. That are frequently used to connect and during charging process then disconnect and reconnect to the working circuit. Cannot recall exactly. What is the voltage of these motors?? You may need 3 positions and ground? Actually, Military spec do have snap lock system for high currents also. We use them for welding transformer quick connects. Signal circuits won't be a problem. I guess. Military spec. connectors, Harting etc
 
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