How to protect a motor controller from the noise coming out of relay

[mingki]

Hi, I am testing my dual motor controller with two BLDC motors(48V, 400W) using this schematic.

Unfortunately, I am having some electric noise from relays so I loose connection with my motor controller randomly whenever I turn on and off the motor.
The connection lose is irregular. Sometimes ok, sometimes lost connection.
The relay spec. is attached.
The relay part number is 702NHDC24V
Can you advise me what protection can I make for the trouble shooting?

 

[itsmoked]

First try to isolate what exactly is causing the crash.
Disconnect each relay one at a time. See which one is the problem. Both?

Once the relay is found reconnect it and remove it's load. See if, in-fact, it's the load causing the problem and not the relay.

Keith Cress
kcress -

http://www.flaminsystems.com