There IS a
delay. I've yet to see the one for the field relay work, but it IS
there.The ones for the armature resistance contactors usually work,
however.Makes me wonder if it is a high resistance in the 'sensing'
wiring concern.
RJ
CZ wrote:
Ok,
so this weekend I literally blew a relay up by moving the lever from
forward to reverse without even engaging speeds 1-3 reverse. Tractor
was moving forward, took speed to 0, then my hand slipped and the
throttle went left.
Boom.
This should not happen. There needs to be a delay in closing the relay
until the armature is at *zero*.
Looking at the schematics, the key seems to be pins 7,8,9 on card 1. 8
applies +36 to the circuit when the reverse switch is closed. 9 is
where the relay is. Between them is an SCR that has to be triggered in
order for the switch to engage R. What seems to control this is 7,
which is a +36 volt line coming from that goes on wire run 8 which
seems to connect to the positive side of the motor after L1 and L2.
>From there it goes to Q105, then into a diode/resistor network which
controls the gate.
I wonder if this is a NOT circuit such that only if there is no power
on 7 will it allow the SCR to energize. Otherwise it holds it off. But
that doesn't make sense, as you can't go from F to R while in speeds
1-5, it's mechanically not possible based on the throttle assembly.
But if you open L1 and L2, maybe there is a residual voltage there till
the motor spins down? Maybe. But what does C106 do?
Hm.
C
through Q105
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