EMERGENCY ELECTRICAL PROBLEM June 21, 2014, 02:19:06 pm Yahoo Message Number: 147019We are in an rv park with shore power. This morning, we lost ac power to the fridge, micro, and outlets--as far as I can tell, all ac power consumers. I know almost nothing about electricity, but have attempted to do a "logical" isolation of the problem. Bottom line results: batteries charge on solar or chassis engine. Batteries do not charge on shore power or generator. Background--our electrical system. We have four power sources: shore, generator, chassis engine, and solar. We also have: Progressive shore power protection unit, whole-house Xantrex 1800W modified sine wave inverter connected to all ac power consumers (including fridge, but excluding a/c), and battery consumption monitor. All 3 of these devices have digital monitor displays that allow me to monitor whether shore power is live, inverter is drawing from batteries or external source, and whether batteries are charging or discharging.Diagnosis / prolem isolation attempt: By watching the battery monitor, it is easy to determine whether the batteries are charging or discharging, depending on the input source. As noted above, they charge when the input source is solar or chassis engine, but discharge when on shore or generator power. These observations were confirmed by a couple of simple tests. I set fridge power source to "auto", with the inverter off. With no active power source, "auto" sets the power source to gas. When connecting to shore power or running the generator, the power source should switch automatically to ac. It does not. Regardless of the coach power source, the fridge runs on gas. Second, I turned the inverter on. As expected, the fridge switches to ac and the microwave display comes on. In this consumption mode, I changed the input power source to the coach to each of the four "external" sources, and watched the battery monitor to determine if the batteries are charging or discharging with the load constant and the input power source varied. The reult with the inverter on and the fridge on ac from the inverter, the batteries were charging when the input power source was solar or chassis engine. The batteries were discharging when the source was generator or shore power. Cause(s)? I have checked the circuit breakers at the the converter and two-breaker panel installed for the inverter. None tripped. Two other possibilites: the converter is a 70amp upgrade per Larry W.'s instructions, including inline fuse (can't remember if it is 30amp or 60amp). Have not yet removed panel to find it. Second, I had installed an inline 300amp T-fuse between the inverter and the batteries, but don't know how to tell if it has blown. So the condition of these two fuses is unknown. Two mure clues. First, last night, when on shore power and attempting to use the microwave normally, it turned on for about 6 seconds and then shut down. It had never done that before. Tried several times with the same result. I reduced the power to 70% and it ran for the requested 66 seconds. Second, today, when ac power failed, despite the Progressive unit showing live shore power with no errors, I turned on the inverter and got an E-5 error, indicating overload or short circuit. I turned it off and back on and the error message never recurred. Sorry this is so long, but I know how many of you want all the details I can provide before you can respond. Thanks in advance. TedNow the interesting part. I have a battery monitor and all during this time it displays increasing cumulative amp consumption from batteries, whether on shore power or generator.
Re: EMERGENCY ELECTRICAL PROBLEM Reply #1 – June 21, 2014, 04:21:29 pm Yahoo Message Number: 147022Bad surge protector or automatic transfer switch.
Re: EMERGENCY ELECTRICAL PROBLEM Reply #2 – June 21, 2014, 04:24:13 pm Yahoo Message Number: 147023Sorry about including the entire message. Dumb iPhone ...
Re: EMERGENCY ELECTRICAL PROBLEM Reply #3 – June 21, 2014, 04:27:38 pm Yahoo Message Number: 147024Well, I've found the source, but I'm not sure what it means (exactly what went wrong and how to fix it). For the last two-three days I have been sensing an odd smell. Not obnoxious and not strong, but definitely a new smell in the coach. My wife could not smell it. I just removed the converter panel cover (the one with the labels for circuit breakers). Behind it is a terminal block, mounted on a piece of black plastic fastened to left side wall of the converter compartment. Connected to the termials are white wires going to the circuit breakers and "disappearing" in a bundle into the hole in the back wall of the visible part of the compartment. The white sheathing on the wires have been burned to a brown hue, the black plastic mount for the terminal block is almost completely melted away, and the faint smell of the last few days is, close up, a strong, acrid odor. Some wires from the terminal block are brittle and broken away from the terminal screws. What happened? Did one or more circuit breakers fail to trip when overloaded? This is a 2004 RB with which we have had no electrical failures. As you can tell from the original message, a lot has been added to the original electric system. The latest service (March 4, 2014) involved: moving the battery monitor shunt from the original battery tray area to under the aft facing seat of the dinette, where 2 agm batteries now reside, hooking the whole-house inverter to the shunt so power consumption would be monitored when the inverter is on, fixing intermittent problems with tank level readings on the SeeLevel II (failed to solve that problem), and replacing the broken cell phone antenna on the roof and the cable from the antenna to the signal amplifier in the coach. To my knowledge, none of this work involved necessary access to the fuse/circuit breaker panel and converter compartment. We have been using the coach continuously since January 19th, the longest it has ever been on the road. What do I do now? Replace the breakers and terminal block? Replace all the burned wire? How do I know it won't happen again?Thanks--Ted
Re: EMERGENCY ELECTRICAL PROBLEM Reply #4 – June 21, 2014, 04:57:20 pm Yahoo Message Number: 147025Bill--thanks for your reply. I should have mentioned that the generator is not linked to the surge protector, but behaves like the shore power. I take it, therefore, that that leaves the transfer switch as the likely culprit(?). Ted
Re: EMERGENCY ELECTRICAL PROBLEM Reply #5 – June 21, 2014, 05:02:49 pm Yahoo Message Number: 147026Ted,You may, or may not, recall that Larry once suggested everyone snug up the terminal block screws now and then. What was once a snug connection becomes less so. No one has said why that is, but I would guess that is because copper is malleable and over time eases itself from the pressure it is under.Anyway, when that solid connection is less so, the local resistance goes up and that in turn causes heat at that spot. Heat may also cause the copper to oxidize worsening the resistance problem. This can happen w/o blowing any fuses or setting off breakers because in fact there is less current drawn then when things are working normally. The problem is that the heat is all in one concentrated spot.I would not replace the breakers, but replace the terminal block and all the burned wire.Alex Rutchka, SE #4 '05 MB
Re: EMERGENCY ELECTRICAL PROBLEM Reply #6 – June 21, 2014, 05:21:19 pm Yahoo Message Number: 147028Bill and Alex nailed it: the problem was caused by loosened connections at the AC terminal block. Replace the terminal block and damaged wiring, and retighten those terminals from time to time. (With power turned off, of course!)Andy BairdTravels with Andy
Re: EMERGENCY ELECTRICAL PROBLEM Reply #7 – June 21, 2014, 05:24:36 pm Yahoo Message Number: 147030Wow! Thanks, Alex. I forgot to mention that we had a little space heater on this morning to take the chill off (as we do every morning on this trip), at the time the we lost ac power. FYI, we are very careful to have only one major power-hungry appliance on at one time: hair dryer, micro, elecric tea kettle, a/c, space heater, etc. (not including fridge, of course).OK, I'll get the supplies and try it out. Very grateful--Ted
Re: EMERGENCY ELECTRICAL PROBLEM Reply #8 – June 21, 2014, 06:20:13 pm Yahoo Message Number: 147032Thanks, Andy. I'm on my way to Ace hardware to replace the wiring, terminal block, and plastic block holder. Question: Is it ok to splice the new wire to the clean old wire that is visible in the compartment? I'd rather not disassemble everything to get behind the rear wall of the breaker cavity. If it is ok, what type of connectors should I use and are there any other cautionary notes to observe?Thanks very much. Ted
Re: EMERGENCY ELECTRICAL PROBLEM Reply #9 – June 22, 2014, 07:20:31 am Yahoo Message Number: 147040Alex nailed it with the loose connection. He also said "No one has said why that is, but I would guess that is because copper is malleable and over time eases itself from the pressure it is under." Consider this - copper expands and contracts with changes in temperature. In a house, your breaker panel's ambient temperature is fairly constant, probably 60 to 75 degrees, so the only thermal differences come from wire heating from load. With properly sized wiring, this is not much of an issue.Our "homes" are different. If you hang out someplace like Arizona, you may see internal temps of 60 on winter nights and 100 by summer days. Further north, if you do not fulltime, the range may well be from below freezing to triple digits. With each such swing, the copper expands when warm and contracts when cool. The difference is microscopic, but copper is a soft metal. When it expands in its screwed-on connection, it deforms, perhaps by the size of a few molecules. When it contracts, the contact can shift, so the next expansion is on minutely different surfaces. Over time, with enough cycles, the surface area of actual contact becomes smaller. This results in more pronounced localized heating due to less conductive area. That greater heating accelerates the expansion and contraction. Add in things like vibration, and after a while, the point of contact can be so small that the heating gets intense. Things like insulation and circuit boards begin to scorch.Ted, you were lucky. Had an actual fire started, you might have lost the rig. This is why the connectors in the ATS and on all breakers and terminal blocks should be re-torqued occasionally.Ken F in OR
Re: EMERGENCY ELECTRICAL PROBLEM Reply #10 – June 22, 2014, 11:27:30 am Yahoo Message Number: 147041Ken--I have purposely left your entire message displayed, as it an elegantly written explanation of the problem in language anyone can undersand. I would expect nothing less from a fellow Oregoniain! If I may impose a little more on your time, can you (or anyone else reading this) answer the question I posted yesterday: can I splice new sections of wire to the remaining wire, to avoid the hassle of tracing each one all the way back and replacing 100% of the original wire? There are four wires, all with white insulation, two solid and two stranded. I have trimmed each wire back a few inches to "good" wire. If the answer is "yes" to splicing, what type of connector should be used? Can I use the old terminal block or should I buy a new one (Ace Hardware did not have the type of block I needed and suggested going to an electrical supply house. Would Home Depot have it?Thanks again for taking the time to explain all this. Ted
Re: EMERGENCY ELECTRICAL PROBLEM Reply #11 – June 22, 2014, 11:31:50 am Yahoo Message Number: 147042I'd try Radioshack first for your cable-splicing needs.. Good Luck
Re: EMERGENCY ELECTRICAL PROBLEM Reply #12 – June 22, 2014, 11:47:57 am Yahoo Message Number: 147043"can I splice new sections of wire to the remaining wire...?"Tempting, but probably unsafe. Any splices would have the same risk of failure as the original setscrew-held terminations, thus doubling your risk... and if they were out in the open, you wouldn't have the protection of a metal box enclosing them. This would certainly not meet electrical code standards.If it were my rig, I'd try to pull out a few more inches of that Romex--enough to allow cutting off the damaged portions and re-stripping and reconnecting the ends. If that proved impossible, then I'm afraid end-to-end rewiring would be the way to go.Andy BairdTravels with Andy
Re: EMERGENCY ELECTRICAL PROBLEM Reply #13 – June 22, 2014, 12:50:58 pm Yahoo Message Number: 147044Sorry I wasn't clear. I have already snipped several inches off each wire, cutting back to what appears to be clean, new-looking wire. There are four wires, all with white insulation--two stranded and two solid. So, I am starting with visible lengths of good wire ready to be spliced. I could try to pull out the bundle a little more, but I think I have lengths sufficient for splicing, depending on the appropriate type of connector. If this sounds ok to you, what type of connectors should I use? Do I really need a new terminal block or can I reuse the old one? It does not appear to be damaged/deformed in any way. I could replace the set screws. Also, the black plastic mounting bracket is completely destroyed so I would need to find one that would work with this size terminal block. I assume I just need to mount the terminal block in such a way as to ensure that it does not come in contact with the metal case.Thanks--Ted
Re: EMERGENCY ELECTRICAL PROBLEM Reply #14 – June 22, 2014, 04:40:30 pm Yahoo Message Number: 147046"I have already snipped several inches off each wire, cutting back to what appears to be clean, new-looking wire... So, I am starting with visible lengths of good wire ready to be spliced. I could try to pull out the bundle a little more, but I think I have lengths sufficient for splicing, depending on the appropriate type of connector."Ted, perhaps I'm misunderstanding, but my advice not to splice still stands. If you have good wires with stripped ends, and they're long enough to reach the terminal block, then no splices are necessary. If they're not long enough, then try to pull out additional length, so that your newly cut ends can reach the terminal block. If that's not possible, then replace the wires completely. But I recommend against splicing, unless you can ensure that each splice is in a metal junction box to protect against the risk of fire."Do I really need a new terminal block or can I reuse the old one? It does not appear to be damaged/deformed in any way."That's a judgement call, but I'd probably replace it to be on the safe side. Its internal contacts might have oxidation or other non-obvious damage.Andy BairdTravels with Andy
Re: EMERGENCY ELECTRICAL PROBLEM Reply #15 – June 22, 2014, 05:29:21 pm Yahoo Message Number: 147047"I have already snipped several inches off each wire, cutting back to what appears to be clean, new-looking wire... So, I am starting with visible lengths of good wire ready to be spliced. I could try to pull out the bundle a little more, but I think I have lengths sufficient for splicing, depending on the appropriate type of connector."Ted, perhaps I'm misunderstanding, but my advice not to splice still stands. If you have good wires with stripped ends, and they're long enough to reach the terminal block, then no splices are necessary. If they're not long enough, then try to pull out additional length, so that your newly cut ends can reach the terminal block. If that's not possible, then replace the wires completely. But I recommend against splicing, unless you can ensure that each splice is in a metal junction box to protect against the risk of fire."Do I really need a new terminal block or can I reuse the old one? It does not appear to be damaged/deformed in any way."That's a judgement call, but I'd probably replace it to be on the safe side. Its internal contacts might have oxidation or other non-obvious damage. I see nothing wrong with splicing new wire onto make the connection. When an electrician wires a house he will bring one feed into a gang of boxes that may have 3 switches and 2 receptacles. He will fasten 5 short wires on to the black wire to supply the 3 switches and the 2 receptacles. Then 2 short wires onto the white wire to supply the receptacles.Scotch locks (Screw on nuts) are the approved way today.
Re: EMERGENCY ELECTRICAL PROBLEM Reply #16 – June 22, 2014, 08:24:26 pm Yahoo Message Number: 147057"I see nothing wrong with splicing new wire onto make the connection". As Andy pointed out, splices are fine as long as they are inside the power center or a metal junction box. In an wood frame RV, you want as much protection against electrical fires as possible. Remember RVs are constantly exposed to hard impacts and vibration, conditions that no house is exposed to and the wire connections take a beating. This type of electrical problem has been well documented here by Terry Tanner, Andy, myself and several others over the years. Occasionally I remind folks to do perform maintenance routines that are not listed in the owner manual's . Checking the body bolts, inspecting the parking brake oil level and tightening all the screw connectors inside the power center are among my favorites. Several time while replacing converters, I have found burnt wires and charred wood in and under the power center. Wires mounted in the open or a plastic junction box might have started a fire. So, IMO, all high voltage wire connection must be made inside metal enclosures. In Ted's case, there may be room behind the power center for a small junction box but would be tight work. It might just be faster to pull new romex and rip out or abandon the old romex. It would also be the time to rewire the surge protector so that it protects all 120-VAC power sources..Larry
Re: EMERGENCY ELECTRICAL PROBLEM Reply #17 – June 22, 2014, 11:23:43 pm Yahoo Message Number: 147072Splicing is appropriate and approved in junction boxes. That is why they are called junction boxes. I challenge you to find an approved power panel installation with splices in it. As we have seen, it is very easy for wiring to heat and cause problems if not installed and maintained properly. Now, on the other hand, if a licensed electrician is here and advises us that splices in a power panel are acceptable, I will bow to his/her expertise. Short of that, I would not accept my opinion or anyone else's suggesting that cutting corners in a power panel is ok.Ken F in OR
Re: EMERGENCY ELECTRICAL PROBLEM Reply #18 – June 23, 2014, 12:25:13 am Yahoo Message Number: 147076As has been previously posted, copper, being a soft malleable metal, will flow under pressure. So the trick is to spread the load over as large an area as possible, not something stranded wire is well suited for.Twisting the wire strands tightly can help, but tinning or soldering the end is not a good idea. While the solder will hold the strands in place, it is also soft and when heated can flow and render the connection looser than without.One method that does work is to use crimp on ferrules like these for 14 Ga wire - other sizes available: Wire Copper Crimp Connector Insulated Ferrule Pin Cord End Terminal Blue(Set of 100) The ferrule is crimped on the wire, providing a gas tight connection, then the ferrule end gets clamped under the screw connector.bumper As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: EMERGENCY ELECTRICAL PROBLEM Reply #19 – June 23, 2014, 12:59:40 am Yahoo Message Number: 147078Splicing is appropriate and approved in junction boxes. That is why they are called junction boxes. I challenge you to find an approved power panel installation with splices in it. As we have seen, it is very easy for wiring to heat and cause problems if not installed and maintained properly. Now, on the other hand, if a licensed electrician is here and advises us that splices in a power panel are acceptable, I will bow to his/her expertise. Short of that, I would not accept my opinion or anyone else's suggesting that cutting corners in a power panel is ok. Splices in power panels and junctions boxes all fall into the same catagorie. It is not alowed to make a splice out side of a box. I has seen this done many times of the job where a new fuse panel was installed. The old panel (100 amp service) was replaced with 200 amp service. And the over head wires were replaced into the new panel. And the job had to be inspected by the city for building codes.
Re: EMERGENCY ELECTRICAL PROBLEM Reply #20 – June 23, 2014, 02:14:26 am Yahoo Message Number: 147079Hi Ted, First, you are lucky that you did not have a major fire. Lucky that your LD did not burn to the ground. Lucky that no human was injured. Now you need to spend a few dollars to repair the minor damage. Based on your description, the electrical arcing was occurring for multiple days, and produced enough heat to melt surrounding plastic [the type that is made to resist heat]. But not enough excess electrical current to trip circuit breakers, although, based on the description, I am not sure which CBs are before or after this box. The arcing may also have damaged/injured delicate electrical and electronic equipment. Pay attention to these items in the next two months. It reminds me of the adventures Andy had after the lightening strike he suffered.Since it is almost impossible to rewire the coach, I strongly recommend extracting sufficient wire length so that they will accommodate/reach a new box. Do get a new box, the long term high heat may have caused unseen damage or impairment. Things inside, and nearby, were exposed to temperatures equivalent to oven baking for multiple days. Again, you were lucky not to have a fire, since wood has an ignition temperature in the 400-550 degree F. range, depending on finish.There are various ways to join two wires. The best is to solder and shrink wrap. Next is to wrap the wires together and shrink wrap. Next is to use electrical tape. Then there are proprietary methods. Look up "butt splices", " butt connectors", "solder butt ", "closed end connector", and "double wall shrink tube". Before you use any method, ensure that it is sufficient for the electrical current and environmental conditions AND that you know how to properly and safely install them.IIRC, in an early message you said you were not familiar with electrical stuff. That means to me that this project is beyond your safe capabilities. Time to hire someone familiar with RV wiring [not a house electrician]. In the meantime, depending on what function [especially safety function] this box served, you might be able to perform an emergency bypass in order to get one or two circuits operational. Again, safety is paramount.I agree with Andy; that it is best practice to avoid splices because they add another point of failure. If they are outside the box [in the open], then they are likely a violation of Code because they are less protected, more likely to fail, more likely resulting in major damage/injury. For homes it is clearly forbidden to have any splice outside a junction box, and the junction box cannot be hidden, etc.; but RVs are governed by a slightly different Code. Someone mentioned twist on wire nuts [knurls]. Knurls are color coded. Different knurls for various gauges, solid or stranded wire. That information can be obtained in any reputable home wiring book. There might be a specialized knurl for your purpose, that info might be in those books. Visit a library with a good home repair section and read every page about splicing, knurls, wire joining, etc. I wouldn't be confident of finding such an item that is safely applicable to your purpose. Due to the vibration in a motorhome, I would avoid twist on knurls; because they can untwist.Harvey
Re: EMERGENCY ELECTRICAL PROBLEM Reply #21 – June 23, 2014, 01:34:51 pm Yahoo Message Number: 147084Is there enough room, and slack on the input, to move the box closer to the shortened wires?ronC
Re: EMERGENCY ELECTRICAL PROBLEM Reply #22 – June 23, 2014, 02:33:22 pm Yahoo Message Number: 147086I am overwhelmed with gratittude for the time all of you have taken to advise on this. I have decided to bring in a mobile rv repair person and am currently searching for one in the East Bay area. My intention is to have him replace entirely the wires that have burned and check out the converter. Although we do not have ac power, we are fortunate to have solar power, so we can limp along, boondocking in an East Bay rv park.Again, many, many thanks for the sage advice form all of you. Ted PS: Sorry about not snipping old text. For reasons unknown, Yahoo is not allowing me to delete it in my reply.
MYSTERY SOLVED: EMERGENCY ELECTRICAL PROBLEM Reply #23 – July 02, 2014, 04:02:48 pm Yahoo Message Number: 147201Thanks to Juli W. suggestion and research, I took the coach to Tim Pease in Fairfield, CA. Juli asked that I report the results. I'm going to do that, because I keep my promises, but you will all have a good laugh at my expense. Normally, one would ask for kindness and mercy, but I deserve neither. As you may recall, an rv park neighbor here in the East Bay generously offered his services as a retired Air Force electrician. He was able to restore all power, except to the fridge, microwave, and ac outlets. He found only four pairs of wires for the breakers, but not a fifth pair for the GFI circuit. Just couldn't figure out what was going on. Tim just informed me that the auxiliary 2-breaker panel installed in the cavity under the fridge had the breakers off. I had turned them off, for safety reasons, when my new buddy started working on the problem. The two-breaker panel was installed when I had a whole house inverter installed and had the fridge wired into the inverter so we could run it on electrical while on the road. So, Tim flipped on the two breakers and power was restored to the fridge, micro, and ac outlets. He will now have a story to tell about yet another bonehead customer. He did replace the original buss bar that we had salvaged. He also said my neighbor's wiring was done correctly and safely. FYI, I also had him look at the intermittent error reading on our SeeLevel II gauge. The manufacturer told me one of the common installation errors is to ground the system to the chassis rather than the negative post of the battery. Tim confirmed that the system was grounded to the chassis, but he doesn't have time today to rewire it. So, at least part of that mystery is solved, but not yet fixed. There are other common problems that he did not explore after finding the grounding was done incorrectly. I'll need to bring it back another time to get it fixed. Thanks to all of you for helping with thoughtful advice about how to do this repair safely.Your now very humble servant, Ted.
Re: MYSTERY SOLVED: EMERGENCY ELECTRICAL PROBLEM Reply #24 – July 02, 2014, 04:53:14 pm Yahoo Message Number: 147202"Tim Pease in Fairfield, CA..."--- Is Tim working independently again or for a dealer or repair shop in Fairfield?Joan
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