Blown 20 amp fuse

[Mark St.]

13,000 gallon above ground pool with T-Cell-5 saltwater generator.
My Aqua-Trol circuit board blows the 20 amp fuse as soon as the cell goes into a chlorination cycle. My local pool store "tested" the cell with a Hayward tester and said the chlorinating cell is good and producing chlorine. I have verified that the pump is not the issue. With the salt cell unplugged from the circuit board, the pump continues to run without blowing the fuse. Any ideas on possible issue? Mark St.

 

[ajw22]

Welcome to TFP.

@JamesW ideas?

 

[C0d3Sp4c3]

13,000 gallon above ground pool with T-Cell-5 saltwater generator.
My Aqua-Trol circuit board blows the 20 amp fuse as soon as the cell goes into a chlorination cycle. My local pool store "tested" the cell with a Hayward tester and said the chlorinating cell is good and producing chlorine. I have verified that the pump is not the issue. With the salt cell unplugged from the circuit board, the pump continues to run without blowing the fuse. Any ideas on possible issue? Mark St.

Am I understanding the 20 Amp onboard fuse does not blow when the salt cell is unplugged and the main board stays On? If so, measure the DC voltage across sides A and B as shown in the below pic. Pls note, you need to wait until you hear the onboard relay click.
Troubleshooting the main board