This is probably a pretty basic question, but I'd like some reassurance that I am doing this correctly.
On the attached diagram the 3 position switch runs the motor CW or CCW. When a limit is reached, the reed switch is opened by a magnet on the mechanical assembly preventing continued motion in that direction.
I am pretty sure the diodes across the relay coils protects my reed switches (and the contacts in my 3-pos switch if it is opened prior to the travel limit). Am I correct?
I am pretty sure the R-C between the motor connection on 0V protects my relay contacts. Am I correct?
For the R-C I think I need to size the resistor to match the cold motor resistance and size the the cap at 1uf and 3x motor voltage - however, the wattage rating of those items is minimal Am I correct? (the duty cycle is low, perhaps one cycle under load for 10 seconds and then a 1 minute dwell).
EDIT - I am 99% sure I have the R-C in the wrong spot. Maybe I can't protect the relay contacts using an R-C when using two relays to switch the motor? Maybe the resistance needs to be greater than the motor? I am confused now. . .
Thanks.
On the attached diagram the 3 position switch runs the motor CW or CCW. When a limit is reached, the reed switch is opened by a magnet on the mechanical assembly preventing continued motion in that direction.
I am pretty sure the diodes across the relay coils protects my reed switches (and the contacts in my 3-pos switch if it is opened prior to the travel limit). Am I correct?
I am pretty sure the R-C between the motor connection on 0V protects my relay contacts. Am I correct?
For the R-C I think I need to size the resistor to match the cold motor resistance and size the the cap at 1uf and 3x motor voltage - however, the wattage rating of those items is minimal Am I correct? (the duty cycle is low, perhaps one cycle under load for 10 seconds and then a 1 minute dwell).
EDIT - I am 99% sure I have the R-C in the wrong spot. Maybe I can't protect the relay contacts using an R-C when using two relays to switch the motor? Maybe the resistance needs to be greater than the motor? I am confused now. . .
Thanks.
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