Controller suitable to run two compressors in tandem

[mac_J]

Would like recommendations for a basic controller, that could be programmed to run two x 4.5kW compressors in tandem mode. 407C gas.

All advice appreciated

[install monkey]

for fridges- just wire them both up and fit a delay timer on the 2nd compressor of say upto 8mins to prevent constant on off cycling.
for aircon eberle do a 3stage controller-adjustable stat-you can fit a remote sensor to it or have it as a room controller

[750 Valve]

What do you want to control the compressors - suction pressure or cooling stages? Refrig or AC?

There are cheap and cheerful controllers that will do both.