series dc motor

I had a customer in a state of mild panic email me today wanting to know how to reverse his dragster WITHOUT using reversing contactors (apparently there is some rule requiring the vehicle be capable of reversing?). On the spur of the moment I came up with a quick-n-dirty kludge that I'm sure...

Hello, This is my first post to these forms. I searched around a bit a could not find an answer to my question, but my apologies if this has already been asked. THis question is also running on the V is for Voltage forums here...

I have a Zapi Sem 0 controller labeled for 24 v. I want to control a 4hp series wound 24V dc motor. Is this possible and how do I connect to the controller? Here are the specifics on the controller: Technical details: Supply voltage: 24 ÷ 36V Maximum current: 150 ÷ 200A High...