Usually a seperate earth wire is run down to the pump as the power cable has a watertight plug which does not accommodate earthing. The earth wire gets fixed to one of the bolts securing the pump to the motor by means of a lug.
Usually a seperate earth wire is run down to the pump as the power cable has a watertight plug which does not accommodate earthing. The earth wire gets fixed to one of the bolts securing the pump to the motor by means of a lug.
This may be an easier solution, but there is an earth wire in the lead out cable to the motor, which is for the earthing process. If this wire has bee left open in the well, this wwill create another situation, in which the water pressure will force itself down the copper wire (just like water down a straw) and finally land up in the motor socket, and in some cases, cause a connection between the prongs of the motor socket, blowing out the motor connection.
This is the reason that a proper junction is critical when joining the motor lead out cable which is approximately 1.5m long and the borehole cable. One tell tale sign of a good quality junction kit is to look at the ferrils supplied. The good quality ones, are not tubes to crimp the wires, but are drilled from either side, allowing an isolation wall between the 2 sides. So if the bore hole cable is nicked to the copper during installation, then water will not run down the cable via the tube which is caused by the copper wire and landing up in the motor socket.
Victor - Knowledge is a blessing or a curse, your current circumstances make you decide!
Solar pumping, Solar Geyser & Solar Security lighting solutions - www.microsolve.co.za
The Franklin submersibles which I installed never had earth wires in their lead out cables. Thus the reason for my external cable. My earth lug, the motor casing and the end of my earth wire were all sprayed with nickel spray which prevents corrosion. My joints to the well cables were all done with scotch kits.
Not sure what motor size you would be referring too, but my experience on Franklin Electric motors up to at least 7.5kW, I have seen both the European and American based lead out cables (difference is the colour of the wires), and they all come with the earth cable, and the actual motor plug and socket has 4 pins. And knowing the company, there is no way that management would even consider to supply the lead out cables with out the earth cable, as this would violate their internal specifications, and to make a physical change like this would cost them millions of dollars in resetting their tooling and automated production lines.
Victor - Knowledge is a blessing or a curse, your current circumstances make you decide!
Solar pumping, Solar Geyser & Solar Security lighting solutions - www.microsolve.co.za
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