Does the lift retrofit kit drain the battery, does it draw current when parked?
The kits draw meaningful current only while moving; for the LFT20 that figure is 10A on average. As long as the switch is not pressed, the motor does not run. When the kit is connected directly to the battery through a fuse the line stays live, so for long parking periods an ignition-controlled supply via a relay is recommended. Repeated raising and lowering with the engine off tires the battery noticeably.
Assess the energy consumption under two separate headings:
- Operating current: The LFT20 draws 10A on average and a typical lift cycle lasts seconds. With the engine running the alternator covers this easily; with the engine off, back-to-back cycles will run the battery down.
- Standby: The LFT20 has no board, processor or sensor, so there is no electronics consuming anything in standby. The LFT54 has an embedded control board; the manufacturer has not declared a numeric standby current value.
On tractors that will be left unused for a long time, the safest approach is to connect the supply line to the ignition signal through a relay. That way the kit is completely de-energised when the ignition is off, and pressing the switch by accident has no effect.
On a tractor with a weak battery, slow movement of the mechanism is not a kit fault; first check the battery voltage and the chassis connection.
Full topic: Converting a tractor hydraulic lever to electronic control