How to control a motor from two remote locations at a distance of 1200 meters?
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This post was last edited by mmkingzm on 2011-1-17 at 15:49. In the workshop, the material pump in the irrigation area is controlled to pump materials into the elevated tank in the workshop； There is a distance of over 1,200 meters between the workshop and the irrigation area; people remotely control the motor using buttons located next to the high-level tank. Local control is also available beside the pump. The motor is protected by a magnetic control switch that operates based on the lower limit signal from the liquid level gauge in the material tank (it serves only a protective purpose and is not involved in the control process). After installation, a test run revealed that the stop button did not work, and the pump could not be stopped. Local control is normal. The control cable was tested with a megohmmeter and showed no faults. This cable seems to have a self-retaining effect ；
Typical motor control includes local and remote control. First, find out where the pump’s power distribution cabinet is; then simply connect the corresponding secondary control components from the cabinet to the workshop – it’s very simple. If the 1200 meters you mentioned refers to the distance between the distribution cabinet and the control panel, it is advisable to use an intermediate relay between the control components.
Should it control start/stop or control speed?
Did the original poster change all the questions? Why? To make a change, just add another one. Otherwise, others won’t know the relevance of their answers! ! !
For a distance as long as 1200 meters, it is best not to use control from two locations. Because of capacitive induction between the core wires of the control cable, very high voltages can be induced. So, the shutdown button will become ineffective!
Reply to 2# jinyuanzhiwang1: 1200m is the distance from the workshop to the power distribution room in the tank farm； Since there are two plant sites, and there are no other power distribution rooms between the workshops and the tank areas, it is somewhat difficult to use intermediate relays!
Reply to 3# zhaohh3211: Control switch!
The electric mouse is quite good; the self-retention feature is really impressive. I thought of that too, but I don’t know why.
The issue raised by Electric Mouse is very crucial; we encountered it last year. So, in the case of capacitive induction, what is an appropriate transmission distance?
Where is the MCC cabinet for the motor located? The irrigation area? The workshop? Or some other place?
Just change the control power supply to direct current.