|
|
05-11-2017, 05:28 PM
|
#1
|
Senior Member
Join Date: Mar 2010
Posts: 279
|
Park Voltage changes with load (50) amp version
Ok here it is! I have verified that the problem is park power related. I bring it to the forum for discussion and maybe help someone else.
The symptoms: L1 = 124 v. 0 amp L2 118 v. 4.5 amp.
Apply load for instance L1 = 128 v. 20 amp
L2= 111 v. 23 amp
Then I get a warning from inverter that one leg voltage is too high and then it would transfer to invert and switch from AC to inverter power. I was noticing the power would change when the water heater kicked in and put a load on L1 and the inverter was on L2. Having had problems with the water heater in the past I assumed it was the problem. We all know what happens when you assume something!! Well anyway I decided to crank the Generator & see what happened. Well everything worked just fine while on generator. So I began checking the park connections, I am working as Park Host here, well I found a few lugs that were a bit loose so I tightened them down. Once again I assumed I had fixed the problem. Well no I didn't solve the problem. So I get the Park maintenance guy to come by and he tells me they had problems here last summer. He checks the lugs & put some dielectric lube on the lugs. But still having problems, but now the high voltage goes to L2 = 128 with load & L1 = 112. Maintenance mans thinks it is related to the neutral. I don't like the smaller gauge wire used for ground.
So anyway the Park is supposed to run new wire to the pedestal about 250 ft. Next Wednesday for the new wire, (maintenance man & myself).So for now we are watching the loads and trying keep the load as even as possible. Propane for water heater and very power conscious.
So there it is park power voltage changes as load is applied. The voltages are constantly changing as the load changes but one goes very high and the other goes low.
__________________
2018 Ram & Beacon 41LKB
|
|
|
|
Join the #1 RV Forum Today - It's Totally Free!
iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!
You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!
|
05-11-2017, 05:38 PM
|
#2
|
Senior Member
Join Date: Nov 2015
Posts: 26,640
|
Neutral IS the culprit.
Smaller gauge wire for ground is OK
__________________
I took my Medication today. HAVE YOU?
Dodge 3500 w/Tractor Motor
US NAVY---USS Decatur DDG-31
|
|
|
05-11-2017, 05:47 PM
|
#3
|
Senior Member
Join Date: Nov 2005
Posts: 7,382
|
Not sure how it might fit in to the discussion but did you verify that the two hot legs of the 50 amp service are indeed phased [eg voltmeter across the two hot legs shows 220/240 volts/not 120 volts??????] Some older camps tried to "upgrade" their infrastructure by using two 50 amp line of the same phase to create a fake 220/240 volt plug?????
__________________
Old Scout
2015 IH45 Foretravel
2003 Alpine 40' MDTS [Sold]
New Braunfels, Texas
|
|
|
05-11-2017, 07:00 PM
|
#4
|
Senior Member
Join Date: Mar 2010
Posts: 279
|
Thanks guys for reply. Old Scout I did measure across the two hots they were about 236 Volts if I remember correctly.
Thanks Old -Biscuit, I agree with you guys that it may be the neutral. We had to rewire another camp site last week and it was a real mess underground. They had spliced the wire between the meter & pedestal. The splice was inside a 4" perforated Pvc pipe about 2 ft long. But the splice was twisted together & taped protected by the pvc pipe! So the neutral it's not surprising that we may find something like that.
__________________
2018 Ram & Beacon 41LKB
|
|
|
05-11-2017, 08:05 PM
|
#5
|
Senior Member
Join Date: Oct 2014
Posts: 7,867
|
Yup, open or compromised neutral WILL cause voltage swings based on load.
Be very careful using power until rewired, or better yet, move to another site until it is VERIFIED correct.
A bad neutral can cause voltage swings that can cost you a lot of $$.
__________________
Brett Wolfe
Ex: 2003 Alpine 38FDDS. Ex: 1997 Safari Sahara. Ex: 1993 Foretravel U240
|
|
|
05-12-2017, 01:37 PM
|
#6
|
Senior Member
Join Date: May 2004
Location: Auburn, CA, Havasu, AZ & Mulege, BCS
Posts: 5,385
|
1. I've seen parks where they used direct burial multi-wire cable w/a woven metallic sheath that was the ground. Worked great till the mildly acid soil corroded the sheath and there was no ground reference back to the service. If pedestals didn't have their own ground and ground/neutral bond then there was an issue at pedestals w/weak or missing neutral.
2. Code is sloppy in addressing ground/neutral bond in RV service pedestals. Here is my recommendation. Every pedestal should be considered the "service" for the coach (whether it has a meter or not) and therefore have its own made ground (rod or Ufer) and ground/neutral bond. Most pedestals are made w/the bond as part of the kit and come marked "suitable for use as service equipment" or equivalent, and most are capable of pairing w/a meter. Meters can be park meters or utility meters. If there is good iron-bearing soil then a 5ft or longer rod should make good ground contact, longer if iron content of soil is weak. Use a suitably rated (listed for exterior use, in contact w/soil) ground rod clamp (not a water pipe type which is for indoor use or above grade).
3. you can say the service is back at some feeder point, but you have to take care w/the neutral so that it is protected at least as well as the hot legs and is uninterrupted from source to pedestal when pedestal is not treated as a service.
4. 250ft is getting to be a long way (how many feet of wire is the issue, not the ground distance). Wire should be upsized to minimize volt drop at that distance. NEC allows #8 wire for 50A, however to maintain volt drop below 5% (figure park voltage may be 5-10V low at heavy demand, then this service loses another 5% for minus 10-16 volts total and you have an issue), at 250ft of wire that should be #6 wire for sure. If the source voltage could go below 115V at heavy demand, this branch could be #4. I'm assuming this is the only service on this branch, if there are multiple services, then wire can be sized based on demand sharing.
5. Another problem in parks that may overload one leg is the L1/L2 constant problem. From a transformer out along a branch of multiple services, most bonehead electricians hook up every pedestal as L1/L2, L1/L2, L1/L2... w/out thinking that RVs may systematically load L1 asymmetrically vs L2 (e.g 1st AC and Micro and some outlets are on L1). Proper practice in a park is L1/L2, L2/L1, L1/L2... as the branch progresses. This is usually easy to fix in the field, just switch the terminations for hot legs at every other pedestal.
__________________
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project
|
|
|
05-22-2017, 03:23 PM
|
#7
|
Senior Member
Join Date: Mar 2010
Posts: 279
|
Ok while waiting on underground lines to be located the Park maintenance man decided to run a Neutral leg from another pedestal and see if my problem was cleared up. Well the problem is still there and he is now saying that it is in my RV. Well it could be, but if so it has to be my power cord and or my my plug, maybe the Surge Guard transfer switch. I have once again ran my Generator with both AC's on, two hair dryers one on each L1 & L2. And also the microwave on the voltages were almost rock steady at 120 & 119 with 35-40 amps on one leg and 20 amps on the other. I feel certain that it's not my from my TS through the rest of my power.
So if anyone has ideas or things to check, that is my job for tomorrow to try and determine where is the problem.
__________________
2018 Ram & Beacon 41LKB
|
|
|
05-22-2017, 06:23 PM
|
#8
|
Senior Member
Alpine Owners Club
Join Date: Jun 2007
Location: Lake Wales, FL
Posts: 3,113
|
Try plugging in to another pedestal and see if you have the same voltages there. When they ran the neutral from another pedestal the issue could still be the neutral terminations in the main distribution panel.
__________________
Dave, Bobbi and Fenway
2005 38' FDTS Alpine Limited, 2016 Jeep Grand Cherokee Limited
Lake Wales, FL
|
|
|
05-22-2017, 08:12 PM
|
#9
|
Senior Member
Join Date: Mar 2010
Posts: 279
|
I have thought of moving to another pedestal, the power is better now it still varies with load but not quite as much. We bypassed the pedestal box. I put the loads to it and I think my inverter may be overly sensitive to low voltage. I had 115 volts @ 35 amps & 118 volts @ 33 amps then my rear AC came on and my inverter flashed on/0ff & low battery alarm and then back to normal operating. I had put my portable progressive PT50 to monitor & keep things in better control. The house wired Surge Guard has been in the circuit all along but I don't trust it. So I will get a new pedestal box wired in to replace the old rusted piece of junk. Thanks for the info and ideas.
__________________
2018 Ram & Beacon 41LKB
|
|
|
05-22-2017, 08:19 PM
|
#10
|
Senior Member
Alpine Owners Club
Join Date: Jun 2007
Location: Lake Wales, FL
Posts: 3,113
|
The voltage varying with the load suggests that there might be a bad connection (high resistance) somewhere. Look at all the blade on the power plugs, they quite often get corroded which causes resistance, take some 00 or 000 steel wool and polish the blades. Check that all connections are clean and tight.
__________________
Dave, Bobbi and Fenway
2005 38' FDTS Alpine Limited, 2016 Jeep Grand Cherokee Limited
Lake Wales, FL
|
|
|
05-23-2017, 05:27 AM
|
#11
|
Senior Member
Join Date: Mar 2010
Posts: 279
|
Thanks I will check all the connections and clean the plug pins
__________________
2018 Ram & Beacon 41LKB
|
|
|
05-23-2017, 06:34 AM
|
#12
|
Senior Member
National RV Owners Club Florida Cooters Club Freightliner Owners Club
Join Date: Mar 2013
Location: Salt Springs, FL
Posts: 453
|
Quote:
Originally Posted by ralph0808
Ok while waiting on underground lines to be located the Park maintenance man decided to run a Neutral leg from another pedestal and see if my problem was cleared up. Well the problem is still there and he is now saying that it is in my RV. Well it could be, but if so it has to be my power cord and or my my plug, maybe the Surge Guard transfer switch. I have once again ran my Generator with both AC's on, two hair dryers one on each L1 & L2. And also the microwave on the voltages were almost rock steady at 120 & 119 with 35-40 amps on one leg and 20 amps on the other. I feel certain that it's not my from my TS through the rest of my power.
So if anyone has ideas or things to check, that is my job for tomorrow to try and determine where is the problem.
|
Based on voltage behavior from original post, I still believe the issue is with the neutral (grounded current carrying conductor). Voltage going up under load while voltage goes down under load on the other conductor is an indication of an open or very high resistance neutral. We call it the windshield wiper issue.
__________________
Jack & Beverly
1999 National Tradewinds 7371; Cat 3126; 6 Speed Allison; 7.5 KW Onan; MS-2012,
2014 Jeep Patriot on a EZE Tow
|
|
|
05-23-2017, 08:13 AM
|
#13
|
Senior Member
Join Date: Mar 2010
Posts: 279
|
They are going to install a different pedestal with clean & tight connections and I will monitor the voltage levels very closely. Wait & hope for the best!
__________________
2018 Ram & Beacon 41LKB
|
|
|
05-23-2017, 10:53 AM
|
#14
|
Senior Member
Alpine Owners Club
Join Date: Jun 2007
Location: Lake Wales, FL
Posts: 3,113
|
Ralph, look at the receptacle blades on the new pedestal, if they are dull ask to have the receptacle replaced. There is resistance somewhere, most likely in the neutral leg. This can be from a loose connection or corrosion. It can be in the pedestal or back in the main power panel, in the connections from the meter box or even at the pole. To get a better idea I would first move to another site and see if you have the same readings. If no problems get the pedestal replaced, if you do have the same readings you need to look at your rig first, you said you have both a PT50 and a surge protector. Check those connections, the connections to your transfer switch as well as the contacts on the ATS. From your comments about everything working fine when on the generator we know that from the ATS on you are good. ATS are known to have an issue with the contacts, particularly if someone has transferred power under a heavy load.
__________________
Dave, Bobbi and Fenway
2005 38' FDTS Alpine Limited, 2016 Jeep Grand Cherokee Limited
Lake Wales, FL
|
|
|
|
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|
|
|