Mike G Posted February 28, 2022 Report Share Posted February 28, 2022 This is my last question in trying to get a 3-phase, 208 volt Paragon SNF 23-3 kiln to fire more than just elements 1 and 7. The only other issue might be the power connector. The 3 wires coming in to power the kiln are not equal: L1 and L2 show needle move between 108-120 and L3 shows 208-220. L3 is the" high leg". L3 goes to the 2 relay switches and L1 and 2 go to the kiln sitter. Is it correct that L3 should be the high leg with the most power? Is there a general rule as to which L should be the high leg rather than the electrician's assumption that it is 3? If this isn't the issue, is it worth donating a kiln to an organization in a large city with kiln repair technicians? (I'm trying to find a place in Texas I can drive it to for repair, as another option, but they have already helped through photos and phone calls and parts.) Thanks- Mike 2371151AFC-Model.pdf Link to comment Share on other sites More sharing options...
Mark C. Posted February 28, 2022 Report Share Posted February 28, 2022 Can these folks help you https://paragonweb.com/support/ Link to comment Share on other sites More sharing options...
Mark_H Posted February 28, 2022 Report Share Posted February 28, 2022 Your sparky needs to meter it. On a high-leg delta system we typically wired the high leg to the B (middle/L2) lug. It should be orange, but not necessarily. Metering each leg to ground, two legs should be pretty close in voltage readings and your high leg will be 2xx volts (typically a weird number.) Only the non-high legs can be used with a neutral to derive your 110v. I'm not a kiln guy but trouble shooting begins by metering from source through the system. I find it close to impossible to walk someone through electrical troubleshooting (beyond basics) over an internet forum. You said elements 1 & 7, I don't see the schematic indicating numbers on the elements, might oughta add them. Link to comment Share on other sites More sharing options...
Bill Kielb Posted February 28, 2022 Report Share Posted February 28, 2022 14 hours ago, Mike G said: The 3 wires coming in to power the kiln are not equal: L1 and L2 show needle move between 108-120 and L3 shows 208-220. L3 is the" high leg". L3 goes to the 2 relay switches and L1 and 2 go to the kiln sitter We need to know what service you have meaning: measure each leg to leg voltage and post. Then measure each leg to neutral or ground and post. BTW I believe Relay #1 by way of SW 1 turns on elements 1&7. This kiln needs at least 200 v between L1 and L2, L1 and L3, L2 and L3 to operate. The voltages you describe seem more like corner grounded delta service. Measure all above and we will have a clearer picture. Without the measurement, there is no way to speculate and without three legs of at least 200 v power all of the elements will never turn on. Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted February 28, 2022 Report Share Posted February 28, 2022 It doesn't really make any sense for only 1&7 to be on unless the relay has fused on. As far as I can see if H1/H2 on the infinity switch are sending power to the coil for the relay then the other SW#1 elements should be on. Link to comment Share on other sites More sharing options...
neilestrick Posted March 1, 2022 Report Share Posted March 1, 2022 2 hours ago, High Bridge Pottery said: It doesn't really make any sense for only 1&7 to be on unless the relay has fused on. As far as I can see if H1/H2 on the infinity switch are sending power to the coil for the relay then the other SW#1 elements should be on. Yep. If 1 & 7 are on, 3 & 5 should be on as well. I'd say this is probably a case of it being wired wrong, which wouldn't surprise me given that it's a pretty goofy setup. Link to comment Share on other sites More sharing options...
PeterH Posted March 1, 2022 Report Share Posted March 1, 2022 21 hours ago, Bill Kielb said: We need to know what service you have meaning: measure each leg to leg voltage and post. Then measure each leg to neutral or ground and post. BTW I believe Relay #1 by way of SW 1 turns on elements 1&7. This kiln needs at least 200 v between L1 and L2, L1 and L3, L2 and L3 to operate. The voltages you describe seem more like corner grounded delta service. Measure all above and we will have a clearer picture. Without the measurement, there is no way to speculate and without three legs of at least 200 v power all of the elements will never turn on. [My emphasis.] I think Bill is right, those voltages would be helpful. PS As a Brit the rich variety of US power supplies seem very strange. Your readings don't exclude the possibility of: From Electrical Service Types and Voltages https://tinyurl.com/2p896wkw Link to comment Share on other sites More sharing options...
Bill Kielb Posted March 1, 2022 Report Share Posted March 1, 2022 6 hours ago, PeterH said: PS As a Brit the rich variety of US power supplies seem very strange. Your readings don't exclude the possibility of: Split phase here is a thing so ……… interesting configurations. And yes, I was trying to speculate why he seems to have only three wires coming in. Link to comment Share on other sites More sharing options...
Mike G Posted March 3, 2022 Author Report Share Posted March 3, 2022 I followed advice here and checked everything. High leg was in the middle and was the orange wire, and power to the kiln was perfect. All volt and amp readings were perfect at connections, cross measuring L1/L2, L1/L3, and L2/L3 good, and elements' power matched the wiring diagram #'s. Turns out that this kiln had sat in storage since the mid 2000's. It had never been fired up til few months ago. There was some corrosion at wires connectors to the elements, and at both switches. The high temps in that first firing with that corrosion didn't allow the required power to reach the elements and made things worse. There is actually a "traveling kiln repair guy" in Central Texas who spent a few hours on it today. He has ordered new relay switches and connectors and will come back with parts Monday. Grateful to him and all your help and suggestions, which I shared with him. Link to comment Share on other sites More sharing options...
Bill Kielb Posted March 3, 2022 Report Share Posted March 3, 2022 5 hours ago, Mike G said: High leg was in the middle and was the orange wire, and power to the kiln was perfect. Where you put the high leg on this kiln does not matter, it doesn’t use a neutral. Any reason the original voltage measurements were so far off? Just curious. Also curious just what type of service you ended up having. Link to comment Share on other sites More sharing options...
PeterH Posted March 3, 2022 Report Share Posted March 3, 2022 7 hours ago, Mike G said: I followed advice here and checked everything. High leg was in the middle and was the orange wire, and power to the kiln was perfect. All volt and amp readings were perfect at connections, cross measuring L1/L2, L1/L3, and L2/L3 good, and elements' power matched the wiring diagram #'s. But what were the voltage measurements? L1 to GND still 108-120 ? L2 to GND still 108-120 ? L3 to GND still 208-220 ? L1 to L2 ?? L2 to L3 ?? L3 to L1 ?? Link to comment Share on other sites More sharing options...
PeterH Posted March 3, 2022 Report Share Posted March 3, 2022 @Bill Kielb Just done a quick sanity check on the diagram. Looking at the elements, and assuming the [L1]...[L3] annotations are correct, gives the following loads. L2-L3 (6.7+6.7) (in series) = 13.4Ω L1-L3 (6.7+6.7) (in series) = 13.4Ω L1-L2 (13.5+13.5) & (13.5+13.5) (in series/parallel) = 13.5Ω So resistance if all in parallel = 1/(1/13.4+1/13.4+1/13.5) = 4.48Ω As power=V²/R, full power P =V²/4.48 From the diagram power is 9600w, so V = sqrt(9600*4.48) = 207.8v Consistent with the 208v stated on the diagram (as phase-to-phase voltage) Link to comment Share on other sites More sharing options...
Bill Kielb Posted March 3, 2022 Report Share Posted March 3, 2022 2 hours ago, PeterH said: @Bill Kielb Just done a quick sanity check on the diagram Calcs look correct, it’s unlikely this delta service is exactly 208v L-L so the power could be significantly higher. Your drawing above is typical of North America 208 v high leg delta service. Just curious what things really ended up to be as three phase delta service derived from a split phase 240 volt environment is unlikely to be exactly 208 v L-L which could / will affect the true power of the kiln, actual required breaker size, longevity of kiln etc… At 240v L-L for example this now becomes prox 12.8 kw kiln, and a 40 amp breaker. My guess is his L-L voltage is 220 volts or more so likely significant and good to know to check all his sizings. Just a guess though at this point. Link to comment Share on other sites More sharing options...
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