Recent content by Gordo

The old Grainger relays were 5Z538 SPST 40A & they had bounce and arcing - and considerable degradation. The new 6CUR4 DPDT 40A has had no bounce but arcs on most cycles, more on the break. Today I did a 2 hr test after changing the HYS from 20 degrees C to 10 degrees. & Cycle Time...

Websters: pitting transitive verb - to make pits in. to mark with small scars. Gordo

Wow, I'm getting lots of good ideas and an education on many aspects, incl safety "heads-up" re this equipment. Appreciate all. Re chatter: See 4th para of my #24 post. Arcing is the issue. Perhaps chatter/bounce is not present now because contacts are new. I'll check hysteresis. Your...

I apologize - didn't see the Page 1 of 2 note, - missed page 2 ...first time on this forum. I again extend a hardy thank you to all! Also, I'm pretty much out of my depth! More background. The kiln is ~ 7"x9"x9" (69" long element 11ohm) just for wax burn-out @ (1350 F.) for the lost wax...

I'll reply to Jim & Wirenut here. I really appreciate the interest/help from everyone on this thread. First, I'm confused...I'm hardly up to speed on this technology. The kiln is 220VAC 20A - 4.4kw Yes, my Fuji PXR4-RAY1 ...the control output supplies only a signal to the 120VAC...

Thanks for the notes. It's resistive. My impression: "less than industrial sized", and perhaps all pottery kilns are resistive...like oversized toasters. I've use mine to warm bagels. Yes, Fuji Electric Systems Company makes controllers that drive SSR's. See my #3 & #6 posts. I appreciate...

Thanks for the ideas. I'll try adding the R & C "protection" - first. Replacement = done. See my #1 post.

Yes, AC. Looks like the industrologic link will help with adding R &C contact protection. Thanks for the help. This forum is really sharp.

contacts that are burnt - pitted, eventually to "weld".

Fuji Micro Controller #PXR4-RAY1-4VoA1 : Power: 100 - 240VAC Measured Value Input: Thermocouple (Type "K" ) Control Output: Relay Fuji Micro Controller #PXR4-RCY " *...

Thanks Dave, but my Fuji controller won't talk to SSR's. A fuji model that will, costs ~ $200. That's a "swapmeet" I can't afford to go to! :-( Gordo

DPST Power relay has 120VAC coil & 40A contacts (resistive) ratings. A Fuji PXR4 Micro Controller is triggering the relay; the load is a 220V pottery kiln element. The contacts are arcing (but not bouncing) at make & break on nearly every cycle. The above relay just replaced a previous SPST...