- #1
mrgilpin
- 2
- 0
I'm trying to refurbish a Heliostat and utilize a computer to control the three phase motors that came with the device. However, I'm having an issue with my control circiut for the three phase relays I've purchased.
I'm using two Struthers-Dunn 645RT series SS motor reversing relays which can be found here
http://www.struthers-dunn.com/images/645RT%20Flyer.pdf
The wiring diagram on the 2nd page shows both the forward and reverse control inputs.
I can get both of these to trigger independently utilizing my digital IO board attached to my computer. However, if both of these inputs are connected simultaneously the relays do not work.
My digital IO board only has a single ground, and if both the forward and reverse control inputs share a common ground, the relay will no longer trigger.
The only way to get one of the control inputs to work is to physically disconnect the ground of the opposite input.
I've tried to install diodes on the ground lines to prevent current leakage up into the opposite control but this also didn't work.
Is there a way to electronically isolate the grounds on these control inputs?
I purchased these solid state relays for the switching speed, however, Struthers-Dunn says that these relays are difficult to control unless mechanical relays are used for the control inputs.
I'm using two Struthers-Dunn 645RT series SS motor reversing relays which can be found here
http://www.struthers-dunn.com/images/645RT%20Flyer.pdf
The wiring diagram on the 2nd page shows both the forward and reverse control inputs.
I can get both of these to trigger independently utilizing my digital IO board attached to my computer. However, if both of these inputs are connected simultaneously the relays do not work.
My digital IO board only has a single ground, and if both the forward and reverse control inputs share a common ground, the relay will no longer trigger.
The only way to get one of the control inputs to work is to physically disconnect the ground of the opposite input.
I've tried to install diodes on the ground lines to prevent current leakage up into the opposite control but this also didn't work.
Is there a way to electronically isolate the grounds on these control inputs?
I purchased these solid state relays for the switching speed, however, Struthers-Dunn says that these relays are difficult to control unless mechanical relays are used for the control inputs.