w7ky
New Member
I'm ready to take my PicAxe deepwell pump control circuit from breadboard to PCB. The recent PicAxe/Mains thread unsettled me a bit. I plan to switch my 240vac 1/2hp pump with a 240vac/75A SSR controlled directly by a 14M. The pump is already in the well, so I don't know the exact amp draw. I think it's around 7A. I thought the 75A SSR mounted to a commercial heatsink would handle the inductive load. Now, I'm not so sure how great the inductive load might be. The pump has capacitive start circuit and the start surge may last several seconds. Maybe I should use a small 10A SSR @ 110vac to control a mechanical 240vac relay.
The SSR, a Magnecraft W6275DSX-1, has the following specs:
Motor Load Rating [rms] 25 A
Non-Repetitive Surge Current (1 cycle) 1150 A
Max. RMS Overload Current (1 second) 150 A
I've been focused on my circuit and code and just assumed I was within tolerance on the 240vac pump/75aSSR/heatsink. I chose the 75A relay because it's the largest SSR in my parts box. The PicAxe and 240 switching are 2m apart. Might the start/stop surge might damage the SSR? I would appreciate your thoughts.
The SSR, a Magnecraft W6275DSX-1, has the following specs:
Motor Load Rating [rms] 25 A
Non-Repetitive Surge Current (1 cycle) 1150 A
Max. RMS Overload Current (1 second) 150 A
I've been focused on my circuit and code and just assumed I was within tolerance on the 240vac pump/75aSSR/heatsink. I chose the 75A relay because it's the largest SSR in my parts box. The PicAxe and 240 switching are 2m apart. Might the start/stop surge might damage the SSR? I would appreciate your thoughts.
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