| Author |
Message |
Keith-Flx-FL (Keith) (65.33.37.243)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 1:10 am: | |
I'm planning my electrical system as we speak. I purchased a 1750 watt 12v inverter as an initial stop gap with the thought it would make a good back up incase the inverter I finally end up with wver goes out. A friend has a 1800 watt 24v inverter he's looking to trade for a 12v... His Crown is all 12v.... Question, Is there an advantage to running a 24v house system? Can you isolate part of the system for those few things requiring 12v, or is it better to stick with 24v bus and 12v house banks? |
FAST FRED (209.26.115.227)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 5:10 am: | |
If you travel regulary the ability of a huge 24V alt to recharge a large house set would be great.
The down side is that many items , (like lightbulbs) are very expensive in 24 and very limited in choices.
IF your planning on a 120V coach, the 24V system would be easier to hook up & maintain than a 12V setup.
Make a list of the toys you "have to have" and see what voltage would work best.
FAST FRED |
Richard Bowyer (Drivingmisslazy) (66.190.119.82)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 8:13 am: | |
And how many light bulbs do you think you would have to replace in the lifetime of the bus? A dozen at the most? At $3.00 per bulb you then have invested less than $50 over a period of ten or twenty years. If this cost is a concern, then you are in the wrong hobby,
Richard |
Geoff (Geoff) (64.1.0.182)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 8:34 am: | |
You are going to need 12v for your house system regardless of which inverter you use. So whether you need a 12v or 24v inverter is answered by asking do you have a 12v alternator or plan on putting one in? If all you have is a 24v alternator then a 24v inverter is what you need. But then you need a 24v to 12v converter (which is not cheap). A lot of the Flx Transit (1980+ models) have both a 24v and 12v alternator, with the 12v alternator running off the V730 PTO. I bought one of these PTO alternator brackets for my RTS and mounted a 12v alternator on it so I am running a 12v inverter with separate house batteries.
--Geoff
'82 RTS CA |
Jayjay (205.188.209.11)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 9:40 am: | |
Go to any CAT or Freightlinr dealer and get a list of over 60 currently available 24V bulbs. I buy 24V bulbs at heavy equipment shops, (across the counter) at less than Bus/NAPA wholesale prices. Same places for 24V guages and instruments. 20% to 60% off retail. Stay away from truck stops too. Cheers...JJ |
FAST FRED (209.26.115.204)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 9:55 am: | |
Its not the cost of the bulbs Richard ,
its the lack of 24V goodies.
Most would chose to use a 120V microwave than locate a 24V unit.
Most will chose a 120v sterio , or a 12v car radio , rather than find a 24V setup ,
most would prefer a 120V blender than attempt to locate a 24V unit.
So the question becomes what toys are important to your life style? And how do they get powered?
Either directly from a 12V system , cause there are tons of 12V toys ,
OR thru an inverter , at which point the 24v single system looks better for house charging than a big expensive & limited output charge convereter.
Unquestionably the easiest DC system to live with has an alternator of that voltage and a 3 stage smart Voltage regulator.
If I were a big time boondocker I would belt a house DC alternator directly to the noisemaker, and have the lowest charge times possable for a big batt set.
With the Coach engine doing the recharge work on the road.
And the Sine wave inverter in charge mode for campgrounds & equalizing.
" If this cost is a concern, then you are in the wrong hobby,"
The cost of bulbs is not the problem , the question is the usefullness of the system to maintain YOUR lifestyle.
Total cost of a nice house bank , inverter and specialized alternator , V regulator , E meter for monitoring and desulfator can run a few thousand with Sams batts & a chop chop inverter.
Tripple that for a good Sine Wave inverter, Rolls or Surette batts , ect.
Hopefully systems discussions by folks that have "there way" will help this gent make a good decision to design a system for HIS needs.
FAST FRED |
Dale Leyten (Fdale) (199.247.177.199)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 11:30 am: | |
I have been thinking of this very same subject for quite a while, and have decided to stick with my 24V system. Headlights are converted to H3 bulbs already. Taillights are a 1683 for a double contact or (what is that other number?) for the single contact. I thought long and hard as to what I would need to run on 12V and came up with flourescent tubes, and an over-the road stereo. The rest will be run on a Trace 4024. A very small (and cheap) 24V to 12V will run all the rest. I already have a 250A 24V battery charger on the 8V71, with new bearings, diodes checked out, and a spare set for less that $20. |
jmaxwell (66.42.92.2)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 1:49 pm: | |
I think your main factor here is which voltage u have for the primary alternator now, most Flx 870's were 12v, but they did make 24v. The auxiliary alternator running on the tranny PTO was usually 36v for the A/C condenser fans only. Also, voltage tap equalizers are not cheap, but then, most 870's that came in 24v primary system were equalizer equipped, so u may already have a 12v equalizer if u have a 24v bus. If u have a 12v bus I would go w/12v battery bank and inverter. If u have a 24v bus I would use a 24v battery bank, inverter, and an equalizer for 12v source. Also, the Statpower type electronic inverters are not designed for hard-wiring into a full distribution system that has any other source of ac electric, such as shore power or gen set, but that is a completely separate subject |
Ross Carlisle (Ross) (216.107.197.90)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 4:18 pm: | |
I went 12V for the house while the bus systems are still 24V. I did this because I didn't like all the gadgetry it took to get 12V from the 24V battery bank.
Life is simple now. The bus is completely separate from the house. I can drain the house completely but the bus will still start. This route was also cheaper than going 24V. All I have to do is install a $75 12V alternator on the engine to charge the house while under way.
I also installed a separate battery for the genset. This way, I can accidentally kill the house bank, but the genset will stil start to charge them back up. If I connected the genset to the house batteries, I would have to start the bus to charge the house bank if I accidentally killed them.
Ross |
Henry R. Bergman, Jr. (Henryofcj) (65.194.145.50)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 28, 2002 - 10:21 pm: | |
Hello Keith:
Our plan right now is to have totally separate electrical systems from the "house" and the "chassis". Crown Super Coach 10-wheeler.
We will leave the chassis 12 VDC system nearly alone and have the entire house be 120 VAC 60 htz running thru a larger sine wave invertor and diesel gen set.
The battery bank voltage (diesel electric coach-no propane) will eventually be determined by cable size expense, battery location and....
The various availabilities of different sized battery chargers and their voltages. Might end up being 24 or 36 VDC. Good luck! |
Dale MC8 (66.52.64.22)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 29, 2002 - 6:27 am: | |
Keith, you might take a look at some of the topics in the not to distant past. I asked for ideas on the choice between 12V and 120V for lighting and got a whole slew of ideas, opinions and suggestions. Some based on experiance and some based on 'what if.' and all of them valuable.
Remember, if you are going to use RV appliances they almost always use 12V for control ckts, refer, furnace, water heater, etc.
HTH. Dale MC8 |
Keith-Flx-FL (Keith) (65.33.37.243)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 29, 2002 - 10:09 am: | |
OK... Sorry JD, I guess I need to keep the 12v inverter for now... I'll know more after Arcadia.
Keith |
Jim Stacy (32.101.44.6)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 29, 2002 - 8:54 pm: | |
If you have a 24v coach, it is probably easier to keep 24V for blower motors and engine starter. A second 12V alternator can then provide for a 12V house bank.
All 12V is the simplest and most convenient. With two 12V banks, you can tie them together automatically for charging by alternator, gen set or land line. You can also tie together for emergency start. Running all 12V means there are no problems with any 24V components, no interface for toad lights, no worries of feeding 24V to a 12V appliance. I traded my 24V starter and alternator for 12V and bought a 3000 watt 12V inverter/charger which easily runs one roof air on the road.
You have to have some 12V, but you don't have to have 24V if you don't want to. FWIW.
Jim Stacy |
Gene Jorgensen (Geno) (172.130.89.115)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 02, 2003 - 10:07 pm: | |
When using a separate 12 volt system in a 24 volt coach (for instance a MC7 which I have) where would you locate the 12 volt alternator when the coach still has the original air air compressor? Would it be possible to use one grove from the generator pulley or are they all needed for the job they were designed for? |
Doug Dickinson (Dougd470) (65.161.188.11)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, January 03, 2003 - 11:33 am: | |
These are all good points! I opted to go with a 24VDC system for all items like an invertor and lighting, and only those absoultely necessary 12VDC items will be 12 volt (like the entertainment radio and some other goodies). I will have a 12 volt battery system, but will use a vanner to charge it off the coach 24V system, (and a cross-tie to the generator battery for backup). I will have a 12V regulated PS for shore power to stay completely off the batteries while they charge and stabilize so I will have 12V all the time I want it. I have the PS and a large Cole_herse switch to do this with. In simple terms, the 24V is for heavy current draw (invertor) and lighting, the 12VDC is for those things that I can't do on 24VDC and are usually a fairly light draw by comparison, and 120V is 120V. All 3 are redundant to some degree.
So - am I nuts to have 12, 24, and 120V systems? Probably, but that's MY way - yours may be different. I like 24V for high current draw and so I can somewhat isolate the surge from large invertor loads starting up. The 24V stuff will see that, but some 24V lighting is all that is affected (most house lights will be 120V).
BTW - I recovered all the 24V bulbs from the luggage rack removal and now have a nice set of spares for low-level lighting. They should last many years.
Doug
St Louis '83 MC9 |