NH ice storm and advice for inverters

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jdemaris said:
For someone who has no other need for batteries - it is not very expensive to just have bank of maybe four 220 AH 6 volt batteries. Hooked in series-parallel they will provide 440 AH at 12 volts. Used with a 3000 watt cheap inverter, and a small generator for recharging them - it's a setup that can run some households on bare essentials - and not have a generator running all the time.

Not having the generator running all the time is why I would want batteries. Not much, but just enough to cover a day, at most. Time to be able to periodically fire up the generator for battery-charging, rather than running it 24/7. With the added benefit that a portable generator can be transported to help out friends and family in need - it only takes a couple hours to re-heat a house if you can get the system powered back up. True, that won't let you comfortably live there, but it will give you another few days before there is a danger of frozen pipes, in a typical house.

Joe
 
The problem I wish to address is" being on the ready " for a power outage. Reference has been made to all the problematic symptoms related to the hassles of being prepared; no gas, can't get to a gas station because of the trees and wires in the road, dead batteries, carburetor gummed up, broken pull cord, my friend borrowed the generator and ran it without oil and so on. I'm as guilty as the next guy. It used to be that the smaller gens I had were delegated to the back of the shop. Two hours of moving equipment out of the way, rebuild the carb, replace the pull cord, make a run to the store for gas, buy some beer( in the old days) drink the beer, forget to buy the gas, finally get everything going for a 10 min run before the power came back on..... but I won !

I have found our big genset is the key for the long haul outages during peak heavy demand usage. We run our household and business with it. It's the off peak times which need to be readily addressed : Keeping the two main OWB circulators running at a lower cost . If you had your way, what would be your choice of options for a good " being on the ready " reliable system?

Bill
 
Weigle Tree Service said:
The problem I wish to address is" being on the ready " for a power outage.

What works for one person might not work for another. Everybody's situation can differ. I put homeowner snowblowers and electric generators in the same categories. Machines that spend most of their lives in storage not being used.

I'm worked as an electrician and as a mechanic for 40 years. Yet, I have problems with my own self-powered gensets - which makes me wonder how people cope who hire out for their repairs. I've got over a dozen generators. They range from as small as a gas powered 500 watt unit, up to a diesel 40,000 watt unit. Many times I'll try to start one that has sat for year or more, and have minor issues. I say "minor" since I have no problem pulling apart a carburetor, or priming a fuel injection pump to get something going. For someone else with no mechanical skills, these problems can be "major", not "minor."

In my opinion, if someone already owns a tractor with a PTO - either full-size or a newer compact - you'd be nuts to buy a self-powered generator when you could opt for a PTO unit.
If not - all depends on what you can do and what you expect. Also depends if you're going to have fuel to run it.

Some areas get many long outages, and some areas may get one outage every few years that lasts only a few hours. Some houses have alternative heating and water sources not needing electricity, and some don't. Like I said, different people and different situations and needs.

Much of this is moot at my home since I have solar-electric with a large battery bank. But, I haven't always had it and we get many power outages. Over the years, I've gotten by fine with a cheap Homelite 4000 watt genset, up to a large PTO generator. They work fine, but I don't like having to run a generator full speed, all the time when electric demands are intermittent. And yes, an inverter-genset is an option that does not run full RPM all the time. They work great. They are also very pricey, and very complicated to repair. Nothing is the ONE solution above all else. I've been building a cabin for several years - in an area with no electricity. I started out running a generator all day long - so I could run power saws and an air-compressor to power my nail gun. Got so I couldn't stand it anymore. Go up to the remote woods to listen to that engine run all day long got on my nerves. Finally put in a battery bank of four T-105 type batteries and a 3000 watt inverter. Much nicer. I run my tools for 2 days and then recharge once with the generator if the sun is not good. If there is sun, I recharge using two 120 watt solar panels. The once glitch is - I don't run the air-compressor from the battery bank. But, I got so that I plan things out so all my nailing sets done in stages- not ad hoc. A get a bunch of rafters, studs, or whatever in place. Then start the gen to get air, do the nailing, and then, shut down.

A few suggestions: Someone who does not own a tractor with a PTO, and does not get many outages might pick up two generators. Chances are you can always get one running. I see many 5000 watt generators for sale used for around $200. That's a small investment. Then, make and effort to run them at least once every year.

In regard to big generators - they often go cheap and are also often simpler in design then small units. The catch is - they are fuel hogs and hard to move. I've bought several that were basically new and unused for next to nothing. Local schools often change out their units every 20-30 years with tax-payer supported "improvements." With my local school, I've bought their Fairbanks Morse 17KW water-cooled, four-cylinder powered genset for $150. It was purchased brand new in 1964 and never used - not even once. Paint is still on the exhaust system. All they did is have the janitors "exercise" it every six months to make sure it ran. This sort of situation is common. In fact - when I bought this one, our school took tax-payer dollars and bought a larger, 50K diesel rig. That was 5 years ago. Now, guess what? They are dumping it. This one has never been used once either. But now - the are embarking on a a $33,000,000 "capital improvement" project. Engineers said it would be easier to buy a new 75KW three-phase genset instead of trying to wire in the old (never used) genset. So, this one will be up for sale soon.

Whatever you do - remember the genset doesn't help if you can't hook it to your essentials, and . . . in long outages - you'd better have a plan for a fuel-source. If you have heating-oil tanks - you can run your diesel from them. If you have a large propane tank - consider a gas engine setup to run on propane. If natural gas? Fine if you can count on your working during a crisis. Gasoline is more problematic than all the rest. It does not store well. That being said, having maybe 10 five-gallons jugs around should not be an issue. With some Stabil added, they will easily keep for two years. Also very easy just to dump it into your car after it's a year old and renew.
 
Jdemaris, You are right referring to the wasted money thrown at " Capitol Improvement " projects. That is how I acquired our Onan 30kw. Water department in the neighboring town needed an up-grade.......same hole in the ground, same pumps' meters and everything else. The only up-grade this 200 hr unit needed by me was an oil change and a set of v-belts and a 325 gal tank of propane. Heck, it's mounted in its own building now with a 200 amp double throw switch for less money than a 10,000w Honda sells for.

I still have a set of 105 batts in one of the trucks which I may " borrow", add a 750w inverter and see if they will keep up with the two circulators during the night-duty ( 8 hr cycle ). My guess would be that a little experimentation before you really need it would be the avenue to take. I'm not under the gun to keep the castle from freezing up and falling into the hands of Old Man Winter.
 
If you are going to use batteries depending on the type of battery will depend on the level of charge to keep them at and the level of acceptable discharge to improve the life of the batteries. IE NiMH batteries should not be charged over 80% and shouldnt be discharged below 20% ( basically what the prius does with its batteries. Wet cell batteries lifespan are also effected by depth of discharge, providing discharge protection will increase the life of your batteries....


Phil
 
mpilihp said:
If you are going to use batteries depending on the type of battery will depend on the level of charge to keep them at and the level of acceptable discharge to improve the life of the batteries. IE NiMH batteries should not be charged over 80% and shouldnt be discharged below 20% ( basically what the prius does with its batteries. Wet cell batteries lifespan are also effected by depth of discharge, providing discharge protection will increase the life of your batteries....


Phil

Usually not a problem when using conventional flooded-lead-acid batteries with an inverter. Most inverters automatically shut-down once battery voltage drops to a certain level of discharge - usually 11 volts.
 
Yes inverters can provide battery protection but it needs to be tested and adjusted. for a 12v lead wet cell battery a voltage of 11 volts is way to low for a depth of discharge protection level. At 10.5 volts typically a 12 volt wet cell will be completely discharged. 60% DOD is the recommended low limit to discharge to, this will bring the battery voltage down ot 11.9 volts. Going lower than that will significantly reduce the batterys life, just as over charging the battery. Maintining a battery float level of 80% state of charge = a voltage of 12.42 volts, maintaining your batteries float voltage higher than that will also reduce its life.....

See this faq page for more on it.

http://www.windsun.com/Batteries/Battery_FAQ.htm#Battery Voltages

~Phil
 
mpilihp said:
Yes inverters can provide battery protection but it needs to be tested and adjusted.

All depends on the type of batteries being used - both for the safe discharge level, and for the way they get recharged and maintained. Most good 12 volt inverters can be set to shut off at 10.8 to 12 volts and have an audible alarm that goes off at 11 volts.

Most good battery companies that sell deep cycle flooded lead-acid batteries state that a 60% discharge rate is fine for normal use, and up to 80% is allowed, when needed without affecting battery life.
At the 80% discharge rate for a 12 volt flooded-lead-acid battery bank - shut off voltage is 11.7 volts.

A good inverter/charger with have many settings depending on battery type, battery bank size, and battery temperature. My Trace when set for deep-cycle, flooded-lead-acid batteries shuts of at 11.8 VDC no-load voltage. The battery company (Rolls-Surette) recommends a safe discharge at down to 20% capacity. It has settings for banks in sizes of 50 amp-hours up to 1000 amp-hours.
Battery type settings include - AGM Gel Cell, Lead Calcium, Deep Cycle flooded lead acid indurtrial or golf-cart type, Ni-Cad and NiFe.

Also, the float charging mode is not sufficent for long-term life of flooded lead-acid batteries. The batteries need to be overvolted once in awhile - via the "Equalize" mode. The "Equalize" mode can be set at 15 VDC or 15.5 VDC for a 12 volt battery bank. Most battery companies require it get done at least every 6 months for a 6 hour time period, and some say every 2 months. Some companies void the warranty if this overvolting has not been done. To the converse - often AGM battery warranties are voided when you DO do it.

Charge voltage gets varied by temperature like this - for flooded lead-acid batteries. At 140 F, a full volt gets taken off the charge-voltage. At 104 F degree, 1/2 volt lower. At 14 degrees F one volt gets added. At 40 F below, two volts get added to the charge rate.
 
There seems to be some really knowledgeable people here. This topic has been bounced around on several threads, so Ill ask some specific questions.

As an average wood burner I was looking at the Tripp-Lite APS 750 or 1250, with at least two Interstate 210 amp-hr deep discharge batteries. I also have a 7550 watt Troy-Bilt generator that is a couple years old, exercised every couple of months but never run for extended periods. (I soon as I bought it we stopped have outages)

The intent, like so many other folks here is to take advantage of the auto-switching function so the boiler remains running when the power goes out even if I'm not home. Run the gen-set intermittently to do normal things like shower, cook (on gas stove) eat, log onto hearth.com etc. and recharge batteries.

1. This is a pulse width modified sine wave inverter. Is this clean enough for pumps, fans and boiler controls? (I've got a Tarm excel 2000)

2. It has a 3 stage 20 amp charger (30 amp for the 1250). I read somewhere that some chargers do not like generator produced juice. Something about the peak voltages. Do you think this gen-set/charger combo will work?

3. My worst case is 620 watts running with all pumps and blowers going. Starting surge will be much higher. Average is more like 120-400 watts. Would a 750 continuous 1500 surge inverter be enough or should I look at the 1250?

4. The switching time is 16.6 milliseconds. Will this cause any problems?

Thanks
 
Greg H said:
1. This is a pulse width modified sine wave inverter. Is this clean enough for pumps, fans and boiler controls? (I've got a Tarm excel 2000)
Yes, in most cases it will be fine. In fact, some of the modified sine-wave inverters are a bit more efficient than full-wave inverters. The only thing that might have a problem is - if you have some type of control with sensitive electronics and an on-board AC to DC power-supply.

Greg H said:
2. It has a 3 stage 20 amp charger (30 amp for the 1250). I read somewhere that some chargers do not like generator produced juice. Something about the peak voltages. Do you think this gen-set/charger combo will work?
No - at least not near like it is designed to work. What is typical is - a charger capable of 30 amps when plugged into grid AC will only put out around 10-15 amps when run from the AC made by a genset. But, you won't know for sure until you check. The general rule of thumb is - any portable AC genset will not make the right power. Most permanent-mounted, more expensive stand-by generators will. Also - portable DC to AC generators - like the Honda or Yamaha inverter series will make perfect power. One other exception or work-around is a 10% step-up transformer. Many solar-electric dealers sell 10% AC step-up transformers that enable standard battery chargers to run off of portable AC generators. Even many combo inverter/chargers specifically made for the solar-electric user will not charge properly from portable AC gensets.

Greg H said:
3. My worst case is 620 watts running with all pumps and blowers going. Starting surge will be much higher. Average is more like 120-400 watts. Would a 750 continuous 1500 surge inverter be enough or should I look at the 1250?
My guess would be no, it would not work and you need the 1250 unit. That is simply a guess based on what I've seen happen with low-end inverters. One example. I have an mod-wave inverter rated 2000 watts full time and 3000 watts surge. When I first got it, it ran a Makita hand-held saw fine (rating 15 amps max steady draw and 1800 watts). Then, after some use it kept tripping its overload breaker. So, I then started using a cheap Ryobi saw that only has a 12 amp draw motor. It too worked for awhile, and then - again - the overload breaker kept tripping. I've had this same sequence of events happen over and over with over makes of cheap inverters. If an inverter rated at 2000 watts won't run a saw rated at 12 amps (1440 watts) - I suspect you too will have similar problems. On the other hand, my very rugged Trace/Xantrex inverter - rated 2000 watts full time - will run any hand saw, all day long with no problems. It's just built much more rugged and much more also. I have two large inverter/chargers. The Trace/Xantrex is my cheaper mod-wave unit. My home runs off of dual Outback full-wave units. Here are the specs on the cheaper Trace/Xantrex 2000 watt unit.

Model D2412 Continuous AC output of 2400 volt-amps and 20 amps at 120 VAC.
Surge rating - 4200 watts.
Efficiency - 94% modified wave
Current draw - search mode is .05 of an amp
in use - .9 of an amp to run the inverter (not make the AC)
Current draw - under full load - 280 amps of DC power
DC charger - 0 to 120 amps
Adjustable load sensing (to turn itself on) - 5 to 100 watts draw

Greg H said:
4. The switching time is 16.6 milliseconds. Will this cause any problems?

Never has for either of mine that don't switch any faster.
 
I have a small generator, it would run my wood furnace fan and a few lights for as long as I have gas for it, I have it back fed to a 220 outlet (yes I have read the warnings of this in this thread, an electrician friend wired it and explained how to use it).
But I also have a Prius. I would like to get a small inverter, something to run the same things. Or maybe I don't need an inverter? The WIKI on this says that the Prius is 220???? Really? how to use a pruis as a generator
I know many on here are great with this stuff. What do you think? Will this work?
 
I think it could be done, but I think the Wiki is a gross oversimplification of the process starting with about step #4: "Purchase a commercial-strength uninterruptible power supply (UPS)" (inverter). That isn't one of the things I regularly look for on E-bay, but I suspect that they are rather rare. However, those that have a 200-250 VDC bus are probably going to put out 240 VAC (more likely to be 480 VAC) and inverters can't be center tapped to deliver less unless you also have a transformer. I would emphasize the warning to consult an electrical engineer before doing this as well as recommend a couple fuses in the circuit to minimize damage in case something goes wrong. You can run incandescent lights on DC, but just about anything else is going to require an inverter. In any event, do you really want to risk the expensive power electronics in your Prius to run your lights?

What would be simpler and less risky would be to get a good size 12 VDC to 120 VAC inverter and connect it to the Prius' 12 volt battery. I bought a 1200 watt Vector for about $130 on sale at Pep Brothers. From what I have been able to figure out, the Prius will cycle the engine to keep the service battery charged when it is left in the "Ready" mode. The DC-DC converter in the Prius is probably limited to 1KW or so continuous, but this will keep your TV on in a power failure. Appropriate fusing would also be a good idea here as well.

The previously mentioned Silverado hybrid has an inverter built in to run 120VAC equipment. It has a dedicated power generation mode that cycles the engine and watches the gauges for you so nothing bad can happen. It will even shut things down if the fuel runs low and you keep the ignition key in you pocket so's nobody can steal your wheels. The military version is supposed to put out about 18 KW, but the civilian version is limited to about 2 KW. I don't have any specific experience, but I know someone who has one and says it works very well. IIRC, they are built here in Baltimore by Allison, hon! ;-)

Chris
 
Is anyone using Tripplite equipment for backup? On Dec. 22 I ordered a APS700HF inverter/charger/trans. switch from Provantage.com, the only response I've received is "order placed with regional warehouse". Provantage can't even respond to a question about backorder status. Has anyone ever done business with Provantage.com? I'm getting pretty close to canceling the order and just getting a small inverter like the one I accidentally destroyed.
 
atlarge54 said:
Is anyone using Tripplite equipment for backup? On Dec. 22 I ordered a APS700HF inverter/charger/trans. switch from Provantage.com, the only response I've received is "order placed with regional warehouse". Provantage can't even respond to a question about backorder status. Has anyone ever done business with Provantage.com? I'm getting pretty close to canceling the order and just getting a small inverter like the one I accidentally destroyed.

If you buy a inverter somewhere else - you might be happier with one that uses a thermally activated fan instead of a fan that runs all the time. Doesn't usually add to the price. Many cheap inverters come with fans that constantly run, and if you using them indoors and close-by, can drive you nuts after awhile. The big cheap inverters that Harbor Freight sells all have the thermal-switched fans and have worked great for me.
 
I just hooked up a tripplite APS700HF 700W inverter/charger/trans switch for a trial run. My load is about 245 watts (one 007 and one 009). The most noticable differenc is now the pumps hum like a transformer and if I had to guess they seem like the RPM's might be lower. Does anyone know what Taco has to say about operating on inverters? I'm running off a pair of 3 year old Walmart marine batteries which are probably 100 to 125 amp/hr each. I'm just over 1/2hr into the run and the indicator light still shows full charge and output measures 115v ac. Now we probably won't have any more power outages this year.
 
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