Some of us put our 64/74VDC locomotives on battery chargers. I've done the "alligator clips on the knife switch" method long enough. I want to install a wired receptacle on the locomotive for that purpose, to mate with a plug I'll put on the battery charger.

Is there a "standard" plug type for this purpose? I don't want to reinvent the wheel here unnecessarily.

Yes, please take a look at what the electric forklift companies use to charge their batteries, they have a well accepted standard plug arrangement.
Mike Tillger

Here is an outfit that sells the standard industrial battery charging connectors with voltage keys commonly used in the applications like Mike described:

http://www.cloudelectric.com/category-s/12913.htm

PC

At WRM, we have a special "maintenance" charger permanently installed on VE 502 (a 44-tonner).

We just have a short 110-volt U-ground pigtail hanging down under the cab to connect to an extension cord for primary power.

I know that Southern Railway and perhaps other roads used a Pyle-National recepticle on both ends of their motors for battery charging. Some of their smaller units (I'm working on an SW-1 currently that's this way) had it mounted under the step on the fireman's side. I believe its still available and I think NS still uses the system on their motors.

Still another option I've seen from "back in the day" was the same pyle connector that coaches and cabeese used for battery charing. A lot of times these were mounted on the battery switch panel on your friendly EMD product.

With all this said, unless you're equipment is going to get out and see the world, it may be that what has been suggested above would be just as good.

Anderson Power Products

http://www.powerwerx.com/

I use their 15amp modular connecters to make custom plugs all the time.


-Hudson

Mike's suggestion to look at what the forklift guys use is a good one. My two Clarks at work have SB series connectors from Anderson. Check then out at http://www.andersonpower.com. I've never had any problems with them in the 7 years I've been at this job.

On the school buses my mother drove for many years, each had a plug on the front of the bus for the expressed purpose of charging the batteries. I'm not the expert in electrical engineering, but maybe something like that will be a better solution. But maybe all that would depend on what you're dealing with. for a smaller industrial engine, like a 25-ton GE, that type of plug would be perfect. For larger locomotives like a GP9, might take a long while to charge the batteries sufficiently just to start the prime mover.

The problem I have with spec'ing a "320A" DIN connection for locomotive batteries is that some people might think this OKs using up to a 320A charge rate, a bit like the argument plaintiffs used in the Firestone 721 tire case. To my knowledge, the max output rate of an EMD auxiliary generator (18kW) is under 200A... and you wouldn't want anywhere near that amperage for most charging, even at momentary peak rate, and if your battery compartment is vented properly, and you have proper control of overcharging. References I have are that the charge rate should never be more than around 75-80A even at peak inrush at the start of charging, and the 'usual' demand rate should be less (considerably less!) than that.

The important thing is to get your voltage regulator DEAD accurate for the external charging. If you're lucky enough to have VRLAs, the 'float' voltage requirements are very tight: nominal 2.25 per cell with swing (temperature-dependent) only from 2.23 to 2.27. There are technical reasons why going outside that range is not a good idea. There are similar figures for normal LA batteries: 2.25 to 2.30 over 88F; 2.30 to 2.33 from 50 to 80F; 2.33 to 2.38 under 50F are the figures Exide gives).

I personally would think that a standard Anderson-type plug, which has high mating pressure to ensure good contact, would be just fine for most sensible-rate charging -- and it's relatively easy to find mating ends. For example:

http://www.amazon.com/Anderson-Type-Plu ... B005C0UQAM

will give you four of the 50A flavor for under $30.00 plus shipping (vs. just under $70 for each end of the DIN-spec connector). You could double these up if you wanted the ability to run the 80-amp initial charge with a safety margin (the high rate isn't sustained for very long if the strings are balanced), without sacrificing the ability to use a single connector for maintenance or trickle charging.

In a pinch you could use something more 'common' like a dryer plug to accomplish the business at bottom dollar. The problem there is that somebody, somewhere, might think you hook 240VAC to that familiar-looking plug... ;-}


If I understand this correctly, part of what you're wanting to do is run some loads at 74VDC in standby, and provide power with the battery acting as a buffer, more or less as if you were driving the auxiliary generator separately, instead of providing 110V access to an onboard rectifier/charger. Just as a reality check, most locomotive batteries are either in 4-cell or 16-cell units, which means that nominal 12V automotive chargers are NOT going to give you the right range of float voltage, to say nothing of the temperature regulation required for long life, unless you tinker with series/parallel connections in the strings, which is just dumb. So you'd either need a purpose-built 110V-to-9.00VDC charger for VRLAs (and please, please note that voltage spec precision!)... you could adapt a big model-aircraft charger to work, but at 9.6V nominal it would be too high even for really cold conventional lead-acid battery float... or get something custom-made with the correct accuracy over the correct current range. (And if you're doing the latter, I concur that it makes more sense to have one unit that connects to relatively cheap connector harnesses, sequentially, than have a separate unit for each locomotive!)

Now, if you're going to do trickle or maintenance charging only, you might be able to adapt smaller 110V units to give the correct voltage-regulating-at-temperature precision at low enough cost to put them on multiple locomotives, and of course the cost of the required extension cords should be less as they're easily acquired OTS instead of needing to be made. On the other hand, you'd then lose the ability to cross-connect 74V to 74V with a simple connection for the analogue of 'jumper cabling' -- which I would think would be extremely valuable if there's trouble away from grid power...


Somewhere in between is the answer to the other implied question I thought I heard: what if you don't run a locomotive enough hours to allow its auxiliary generator and regulator to put full charge back into the batteries, particularly on days when high cranking power is required for starts? Or if the engine idles a lot and the aux gen in your particular locomotive doesn't produce, or hasn't been modified to produce, good amperage at low speed? You'd want the ability to TRIM the external charge so the net V from both 'idling' aux gen and external source is right where it ought to be for float spec at ambient battery temp (not outside temp) and stays there as the battery V comes up to full-charge spec.

There is probably scope here somewhere to discuss how accurately locomotive voltage regulators are set, and how they do temperature correction for battery-box temperature rather than whatever is happening outside ... but that's for another thread!

Interesting. I see a few people made a lot more out of my question than I actually asked. All I wanted to do was plug and unplug a battery charger so we could use the charger on multiple locomotives, without the risks involved in clipping alligator clips to the knife switch. Interesting information though.

So there is no "standard" for locomotives.

I see where there is a standard for forklifts, with a dozen Anderson connectors for different voltages, all colored and keyed different. http://www.andersonpower.com/products/colorcode_mp.html However, their convention is to count each battery as 2.00 volts/cell, so a locomotive battery is "64 volts" (not really). They don't have any color codes for that. The closest is green, for 72V, and you're rather unlikely to have a 72V forklift, but if by chance you plugged a real 72V charger into a locomotive, you'd blow up the battery pack. Or there's blue, for 48V, which would simply fail to charge the locomotive (assuming it has diodes), but you are more likely to have a 48V forklift around the shop. It's a common golf cart voltage for instance.

Hmm.

I'd argue that there IS a standard for locomotives, it's just not a "forklift" style connector.

EMD (and I would assume GE and Alco as well), for many years, has used a large, coaxial plug, originally available from Pyle-National. This same connector was also used for battery charging on cabooses and passenger cars.

(see #12 in attached picture for the matching jack, in an SD40-2)



My suggestion would be to use the Pyle style plug if possible, but NOT to attach it directly to the charger. Instead, use either a "twist lock" style connector (as used for 220V extension cords), or a forklift style connector (or the connector of your choice) on the end of the charger cord. You may then make up several "adapters" consisting of the mating connector to your charger cord, a foot or two of wire, and one of the following:
1) the Pyle plug
2) any other connector to match "non standard" charging jacks already installed in your equipment
3) a pair of alligator clips, to accomodate any equipment that does not yet have a charging jack installed (hey, unless you only have ONE locomotive, this project will not happen overnight! )

At IRM we use the system described above, on all 3 of our chargers, utilizing the twist lock style plugs. I believe each of the chargers has 2 cords, and with the "adaptors" removed, there is no exposed "hot" metal for an overly inquisitive visitor to come in contact with, when a cord is "live" but not in use. The forklift style connectors may have openings large enough for little (or big...) fingers to slip in and make contact with "live" connections.

Jeff

When McHugh Bros. bought Hoboken Shore RR 700 about 1975, it had that Pyle National style connector for the engine heaters, even though they ran off high amperage Alternating Current.

FYI:

The 2 pole receptacle located on the end plates of SR (NS) EMD units is shown as EMD p/n 8176771. Rating is 200 A and application is shown as "battery train-lining."

There are (3) p/n's shown for the plug that would fit into the receptacle shown earlier within the thread:

8062828-Plug 2 pole metal body

8345699-Plug 2 pole phenolic body

8352002-Plug 2 pole rubber body

DPK

Have you tried Trans-Lite in Milford, CT? They acquired some of the Pyle line.

The other thing that comes to mind are that many passenger cars seemed to have a fairly standardised charging receptacles / plug arrangement.

Gord

Have you tried Trans-Lite in Milford, CT? They acquired some of the Pyle line.

The other thing that comes to mind is that much passenger rolling stock seems to have standardised charging receptacles and plugs.

Gord