| Author |
Message |
Les Seiler (Lester)
Registered Member
Username: Lester
Post Number: 8
Registered: 11-2006
Posted From: 67.158.79.240
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 19, 2007 - 10:15 pm: | |
Parked in a campground that has a 30 amp service,you have an inverter that's hooked up to four 8D batteries. It is a 24 volt system. You plug into the 30 amp shore power. The inverter is shut off. If you are drawing more than 30 amps in the bus, will this run the batteries down? If this is the case, please explain. If you are using more than the 30 amps, should it not kick the breaker on the post outside?
Lester |
david anderson (Davidanderson)
Registered Member
Username: Davidanderson
Post Number: 220
Registered: 2-2004
Posted From: 69.153.72.127
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 19, 2007 - 11:01 pm: | |
The way you explained it, (inverter off) yes the batteries will go down. Now if you turn on your inverter and it has the ability to load share, ie. you set your shore line input cable size to 30 amps then it will draw up to a maximum of 30 amps from the pole and shed as many amps needed to avoid exceeding 30 amps. It will shed the power to the battery charger and even go neqative and draw from the batteries if needed to avoid tripping that power pole breaker. It will do this ONLY on the loads it senses through the inverter.
If you are dogboned from a 50 amp cord to a 30 amp cord you may have circuits in your wiring that do not go through your inverter like an air conditioner or water heater, perhaps. If so, then you could trip the shore power breaker. At that point the battery bank will attempt to power everything that is wired through your inverter output that happens to be on when the breaker trips.
I had this happen once in my bus. I have a 50amp system and I dogboned to a 30 amp pole. My microwave and front AC are on the inverter. My middle AC is on the other leg. I had both AC's running and my wife turned on the microwave. POOF, all power went dead. I turned all the switches off and reset the power pole. The inverter was now dead. Hmmm, I went in the bay and found I had blown my 300 amp DC fuse on the battery bank. That was a $25 cup of coffee. See what happened??? The inverter cannot sense that 2nd air conditioner because it is on the other leg which doesn't pass through the inverter, but the 30 amp breaker on the power pole did. Consequently, the battery bank tried to pick up the microwave and front AC. No can do. I didn't design for that.
This is the way my Trace SW2512 works in my Eagle.
Give us a little more information about your inverter and wiring panels. Size, brand, etc. Wiring panels? 50 amp 240 volt or 30 amp 120v only. |
Les Seiler (Lester)
Registered Member
Username: Lester
Post Number: 9
Registered: 11-2006
Posted From: 216.75.182.138
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 20, 2007 - 12:10 am: | |
David
We have a 3600 watt Trace inverter-DR 3624- four 8D batteries- 24 volts. We are installing a 60-10B Vanner equalizer. The 12 volt will come out of one the batteries. In order to keep the batteries charged, the inverter will have to always be on when plugged into shore power. Am I right? What size equalizer do you have? This one only puts out 10 amps. I am not sure this is enough. we have 50 amp.
Lester |
George M. Todd (George_mc6)
Registered Member
Username: George_mc6
Post Number: 303
Registered: 8-2006
Posted From: 76.168.69.233
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 20, 2007 - 1:26 am: | |
Les,
You have thrown out a whole bunch of questions and variables, here, so lets try and figure some of it out... You tell us a 30 amp park service and inverter off, NO your batteries won't run down if you are only using 120 Volt loads. If you exceed 30 amps of 120 Volt draw, you will trip a breaker. Now, if you have an expensive inverter that will share load, and you draw more than the 120 Volt current limit setting, say 30 in your case, the inverter will draw 24 Volt current from the batteries and make 120 Volt AC out of it and add it to the 30 out of the shore power. Remember that 10 amps of 120 V equals 50 amps of 24 V with a perfect inverter, which doesn't exist. So 10 Amps of 120 V = about 55 amps of 24 V.
I am confused by your comment about "The 12 volt will come out of ONE of the batteries." If true, that is a recipe for greatly reduced battery life and output capacity. That is also why you install an equalizer. There is a post below, that is only a week old concerning a bus with both an inverter and a converter, and boiling batteries. The converter is un-needed, and the batteries are being boiled because the 12 V is taken off of one battery, and when charging current is applied to the series pair, (you have two) it greatly overcharges the unused (still charged) battery, and the used (discharged) battery doesn't get enough.
Are you talking about having a 50 amp 120/240 V AC shore power connection, and a 10 Amp 24 V DC equalizer in the same sentence?
We need much more info!
Curious George |
Les Seiler (Lester)
Registered Member
Username: Lester
Post Number: 10
Registered: 11-2006
Posted From: 69.63.63.67
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 20, 2007 - 12:45 pm: | |
George
On a 60-10B Vanner equalizer there 3 lugs. From left to right- +24 volt , 12 volt , and ground. We have a 4 battery 24 volt system. How do you think this should be hooked to batteries to get 12 volt DC?
Les |
david anderson (Davidanderson)
Registered Member
Username: Davidanderson
Post Number: 221
Registered: 2-2004
Posted From: 69.153.72.127
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 20, 2007 - 2:18 pm: | |
Sorry Les,
I will have to defer to someone who has a 24 volt inverter that has experience in tapping 12 volts and using an equalizer to keep the battery system balanced. Since my Trace SW2512 is 12 volt I don't have the issues you have.
To answer your question, yes the inverter will have to be on to when plugged to shore in order to charge your batteries, and you wrote above that you have a 50 amp cord. Because of that, the situation I described about my microwave and air conditioners will apply to you IF you have non inverter loads within your system. You should be able to determine which loads pass though your inverter and those that don't by plugging into a 50 amp post, turn off the inverter and turn on appliances. Those that operate sans the inverter are on the non inverter leg. Those that won't operate will be on the inverter leg.
David |
David (Davidinwilmnc)
Registered Member
Username: Davidinwilmnc
Post Number: 204
Registered: 7-2005
Posted From: 152.20.216.103
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 20, 2007 - 3:12 pm: | |
Les,
The ground on the Vanner eq. connects to the ground. The 12 volt terminal connects to the pos. terminal of the 2nd battery. This is also where you'll attach your 12 volt loads. The 24 volt terminal connects to the last terminal, the 24 volt positive terminal of the 4th battery. Mine's an 80 amp equalizer, so I have an 80 amp fuse on the 12 volt cable and a 45 amp fuse on the 24 volt cable. The equalizer will keep the batteries 'balanced' up to it's limits (i.e. current rating). A 10 amp EQ is a bit small, in my opinion.
Here's all you'll (likely) need to know: www.vanner.com/pdf/man-0001.pdf
David |
Stephen Fessenden (Sffess)
Registered Member
Username: Sffess
Post Number: 720
Registered: 1-2002
Posted From: 66.38.120.219
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 20, 2007 - 10:08 pm: | |
The inverter should not run down the batteries when it is off. On my Heart inverter the inverter still charges the batteries when the inverter is switched off at the inverter.
The inverter should not draw battery power when it is off, but it may still charge the batteries. You will only have to recharge the batteries when you have run them down from 24 volt and 12 volt loads, like the refrigerator and heater electronics, 12 volt lights, radios, diesel heater, etc. You should be able to go several days easily without charging the batteries. I turn the 120 volt circuit breaker to the inverter off when I cannot afford the 120 volt power to charge the batteries, such as when using microwave, toaster and coffee maker. Then I turn it back on when the 120 volt load is lower.
On wiring your Vanner, fuses: You can use two 40 amp fuses in parallel to equal one 80 amp fuse. That information came from Vanner and it is how mine are wired: one forty amp fuse on the 24 volt Vanner wire and two 40 amp fuses in parallel on the 12 volt Vanner wire. I have a 60 amp Vanner Equalizer. The equalizer will keep the batteries balanced even though there is no charging going on. |
Jim and Myrna Lawrence (Daffycanuck)
Registered Member
Username: Daffycanuck
Post Number: 42
Registered: 10-2004
Posted From: 66.82.9.82
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, November 21, 2007 - 11:06 pm: | |
I have a 4024 Trace inverter which has a battery equalize function.
When using a 'battery equalizer' for 12 volt loads, the supplied voltage will be exactly 50% of the 24 volt batteries.
When using the inverter battery equalize function, the voltage to the 24 volt batteries can be quite high. e.g. I have mine set to 30.5 volts, therefor the 12 volt supply voltage is 15.25 volts.
The higher supplied 12v voltage COULD damage some 12 volt appliances.....such as the 12 volt control on a fridge.
Just something to be aware of.... |
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