Wiring a furnace to run off an extension cord.

[mm]

Oh, yeah. You're right.

They should mark the brand on the ends too. It's probably a sleezy trick by the makers to avoid paying out when they leak.

Yeah, the AA are 1.2 volts and the batteries-in-camera plug-in charger (not included) is supposed to be 5 volts for 4 of them. If I eventually try to use these in a penlight, I don't suppose they will work. Not enough voltage.

I don't remember how dead they were when I stopped using the camera last Jan. or Feb, but on election day, they were totally dead. They seemed to charge up fine but I haven't tried to use them or to measure their voltage.

The other set, in the fridge since last January, were still 1.24 or

1.26 volts when I took them out last week.

[clare]

Backfeeds?

How the heck do you get a backfeed when you unplug something from one power supply and plug it into another one? Absolutely IMPOSSIBLE.

What he has is a double pole, Infinite throw,break before make, manually operated switch. Can't get better backfeed protection than that.

[clare]

NiCads loose about 20%? charge per month - they are USELESS for standby power apps where they sit unused for months, and are then expected to work.

[James Sweet]

They do, and so do conventional NiMH batteries, but there is a new breed that does not suffer from this problem. Look up Sanyo Eneloop, there are a number of clones, known as low self discharge, hybrid, etc. I've been using mostly Eneloops in my stuff and they live up to their claims, and will hold roughly 85% charge over a year of sitting. I've heard some others are about the same, only ones I've had any real negative experience with were Tenergy, they're cheap, but worthless.

[mm]

Mine were NiMH. That's what the camera shop was pushing.

[mm]

I don't think that describes mine, even though mine kept their charge for 9 or 10 months in the fridge. I bought them a year ago. I don't know if that is older than the new breed. This is all it says on the label:

They are GP2000 series, made in Malaysia, product of Gold Peak Group,

200AAHC, 1.2V typical 1950mAH

Standard charge 16 hours at 190ma.

I bought the camera and the batteries while traveling, not in America.

[James Sweet]

If they don't specifically say low self discharge, precharged, or hybrid, then they are conventional NiMH batteries. Storing them in the fridge will indeed reduce self discharge of either type.

[gfretwell]

I have been in discussions with inspectors about this and the only real NEC violation with a cord and plug connected furnace motor is the manufacturer's installation instructions don't say you can do it. On the other hand I have never seen instructions that specifically said you couldn't. If you said you were doing this to make the blower easier to service, THAT is legal. Considering the other alternatives I do not see this as the most unsafe option. Keep the pigtail with the cord and plug as short as possible to minimize the damage potential, use a good "hard service" cord with a proper cord grip on the blower end and a molded plug and "rock on" IMHO.

[Ed Pawlowski]

Technicality, but the motor wiring is not touched, the main wiring (control) box is.

[clare]

The code requires a manual disconnect within X feet of the furnace. This is USAUALLY assumed to be a switch. A plug serves the same function and is easier to tie down (disable for service)

[clare]

And the only Gold Peak batteries I've ever owned were absolute trash. Mabee if they were kept in the fridge instead of used mine might have lasted longer??

[Twayne]

Impossible isn't what it's about. POSSIBLE is what it's about, and to use a generator, you need a transfer switch. What I think I left out is that his local code enforcement office is going to have the final word on the subject; that is where he has to check. If they allow it, it's legal. If not, it's not. It's easy to call & ask rather than put up with rhetoric in places like this. He's going to need a transfer switch that guarantees never backfeeding; nothing guarantess he won't hook it up in a manner that could backfeed, whether he intended to or not. Plus, he's not the only soul on earth that might use the generator - they don't accept taht as an arguement. Only positive situations are allowed, not promises.

[bud--]

Having a plug-and cord connected blower motor for servicing should be code compliant. I don't see how cord and plug connecting a fixed in place furnace (the OP's plan) is permitted.

Aside from the code, the plan sounds practical and safe.

[Steve Barker DLT]

just a regular old grounded pigtail and a standard outlet will do just fine. That's the way my HVAC guy installs all furnaces. That way the plug serves as the disconnect required to be within vision of the furnace serviceman.

s

[James Sweet]

Furnaces around here are all wired with armored flex, usually a standard light switch in a box on the side as a disconnect. I see no safety issue with using a pigtail plugged into a receptacle to power the furnace, but local codes may say otherwise, it's worth checking.

[mm]

Maybe.

OTOH all I know is that they didn't lose a charge in the last 10 or 11 months.

I bought the camera about a year ago, and only used it daily for about

2 weeks, and then a day or two 2 weeks later. I'm not sure I ran this set of batteries down more than once. (Because when i bought a separate recharger, I ended up with two sets.

So I still don't know how many times I'll be able to recharge them, and I'll never know, because this is not the kind of thing I'll remember. And since I ended up buying a second smaller, cheaper digital camera, that I use far more often, with a different kind of battery, I may only charge these AA batteries once a year and if they only last say 4 charges, i won't know if that is because they weren't good batteries or because they're 4 years old.

Now if they take 10 full charges over ten years, I guess we'd all call them good, but I won't be able to tell you that for another 9 years.

[Mark Lloyd]

Any reason it needs to be that complicated? No need for a switch at all, just put a regular plug on the wires going to the furnace and move it to either a regular receptacle or an extension cords.

[zxcvbob]

Use a single outlet, not a duplex. And a nice armored plug. Keep everything short and neat.

Bob

[James Sweet]

And check local codes. It should be perfectly safe, but code is not always logical, and just because it is safe does not mean it is legal. That naturally doesn't stop a lot of people, but I like to keep things up to code whenever possible, reduces the chance of liability.

[bud--]

A switch and an "inlet" isn't much more complicated.

The NEC limits the use of cords to connect equipment (422.16 is relevant). Cord and plug connection is permitted for maintenance and repair or frequent interchange. (Specifically alloweded are garbage disposers, range hoods and wall mounted ovens.) If boilers and furnaces were allowed to be cord and plug connected you would probably have receptacles provided, and boilers and furnaces would come with cords the HVAC installer would plug-in. (Would there be an electrical inspection? If there was no furnace circuit outlet would someone connect to a general use outlet with an extension cord?) IMHO hard wired is more reliable for an essential function.

As I said in another post "aside from the code, the plan sounds practical and safe."