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bi-directional voltage spike suppressor for DC PM motor

I have a 12 VDC motor, 0.9 horsepower, that I need to cycle frequently in both directions. The motor (a winch motor) is being underutilized for what I am doing with it. The duty cycle looks like this: It is biased in one direction for about 2 seconds with about a 40 amp steady-state draw (but a substantial in-rush I am sure), then rests for about 15-30 seconds, then it is biased in the other direction for about 2 seconds with about half as much draw, but probably the same(?) in-rush and then it rests again for 15-30 seconds.

I am failing the mechanical relay contacts in this application, I am guessing because of the frequent arcing on the break of the contacts. Can anyone recommend a solution for absorbing the flyback in both directions? Thanks in advance.
 
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There are varistors, and there are bidirectional transient absorber diodes available.
What's the rating of the relay, and approx how many cycles does it take to fail it?
 
300-400 operations, sometimes as high as 500

I would say that the relay seems to be done at around 300-400 actuations. It is a ZJSF-11B rated to operate at 12VDC. In terms of # of operations it is rated for, I can't find that spec.
 
Would using an ICL to limit the in-rush help prolong contact life, as long as the delay that is induced is still acceptable?
 
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