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| Electrical Issues: Hatch Lift - Battletech Pod - Tail Gate Lift Motor |
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| PL1:
--- Quote from: kahlid74 on January 22, 2013, 10:33:03 am ---PL1, what are the limit switches for? --- End quote --- Video from Griffindodd's monitor rotation tests show limit switches being hit by the washer/bolt. The limit switches are there because your motor/actuator has a longer travel distance than it takes to open/close the hatch or turn the monitor. The switches are wired to the Normally Closed (NC) contact. When not pressed, they are in the closed green position. When pressed, they are in the open red position. Your hatch starts in the fully up position with the upper limit switch pressed. When you press down on the DPDT, the + voltage is applied through the lower limit switch to the "Down When +" and ground is applied to the "Up When +". As you hold the switch down, the motor lowers the hatch until it presses the lower limit switch. When the hatch presses the switch, the NC terminal is disconnected from the common (red position) which stops the motor from going lower even if you are still holding the switch down. When you press up on the on the DPDT, the + voltage is applied through the upper limit switch to the "Up When +" and ground is applied to the "Down When +". As you hold the switch up, the motor raises the hatch until it presses the upper limit switch. When the hatch isn't all the way up or down, you can move it up or down at will since both limit switches are closed. (green position) Long lever arm microswitches will give you a more precise adjustment of the stopping point. Avoid nub microswitches, they lack the desired travel between actuation and bottoming out so you don't damage the switch. If possible, rig two bolts so one head hits the upper limit switch and the other one hits the lower switch. Use a tee nut to hold the bolt and a second nut tightened against the tee nut to lock the bolt in place Scott |
| kahlid74:
I would have to find limit switches that support 20-40 amps at 12 volt. Interesting idea. |
| BadMouth:
--- Quote from: kahlid74 on January 22, 2013, 12:10:40 pm ---I would have to find limit switches that support 20-40 amps at 12 volt. Interesting idea. --- End quote --- I'm having trouble believing that thing draws that much current, especially if it had gas struts helping it. |
| kahlid74:
--- Quote from: BadMouth on January 22, 2013, 12:33:52 pm --- --- Quote from: kahlid74 on January 22, 2013, 12:10:40 pm ---I would have to find limit switches that support 20-40 amps at 12 volt. Interesting idea. --- End quote --- I'm having trouble believing that thing draws that much current, especially if it had gas struts helping it. --- End quote --- I agrees completely but I was just going off the electrical troubleshooting guide from Honda. |
| PL1:
--- Quote from: kahlid74 on January 22, 2013, 12:10:40 pm ---I would have to find limit switches that support 20-40 amps at 12 volt. Interesting idea. --- End quote --- Just looked for high amperage limit switches. :o :badmood: You'll save a LOT of money changing this circuit to use relays to connect the high amperage up and down power to the motor. Use a SPDT switch with up connected through the upper limit switch to the coil of the relay(s) connecting the high amperage power supply to the motor in the up direction. The SPDT switch down is connected through the lower limit switch to the coil of the relay(s) connecting the high amperage power supply to the motor in the down direction. The ground connections on the relay coils are always connected to ground. Scott |
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