Generally,Series Motor Controller and Permanent Magnet Motor Controller need reversing contactor if you want to achieve reversing.Separate Excited Motor need not.

Contact Ratings
Contact Form 2Z
Contact circuit Voltage and loading current(resistant) 84VDC Max 400A
20+-5C cold state max motion voltage(VDC) Pick-up <=70% of rated voltage
Drop-out 5%-30% of rated voltage
Machanical life(Min.) 100,000 Ops
Electrical life(Min.) 50,000 Ops
Coil Ratings
Coil rated voltage 24V,36V,48V,72V,84 VDC
Max coil current under the rated voltage 0.1A
With 20+-5C cold state starting coil max current

Specification:
Insulation Resistance 100Mohm Min.
Dielectric strength Between Contacts 2000VAC.
Between coil and contacts 1500VAC.
Environment temperature and attitude -40C-+85C; 0-20000m
Max relative humidity 98%
The shocking of fixed point 1 Frequency(11Z) 10-200
Acceleration(g) <3.5
Shocking Speed(time/min.) 60-100
Acceleration(g) 4
Constant acceleration 8
Operation regulation Continue
Installation direction Random