Mobile Power Needs

[Anonymous user]

Here is the scenerio:
I work for a sports timing company who uses RFID Tags "Chips" to track athletes progress during a running, cycling, skiing event, etc. These events are usual held in locations that do not have access to a reliable power source, except for the use of a generator. Currently, we have a dodge sprinter with a built in "power supply". This supply is of unknown origin and has been troublesome in our need for power. It seems to be on its last legs and we are looking to replace it since it does not meet our power needs.

What we would be looking for would be to power a variety of equipment within our sprinter including servers, monitors, laser printers, displays and charging equipment for phones and radios. I estimate we would need a max load of about 4000W.

The input power needs to be able to handle a few sources; vehicle alternator, 120V generator or grid, and future solar panel.

I would like the system to last as long as possible, our current equipment has 4 car batteries and I would consider upgrading to more. An external display for the status would be helpful too.

Can anyone suggest a solution to my problem? Thanks!

[TheNotoriousKMP_apc]

I think the APC UPS's and compatibility with Solar Paneling anytime in the near future is going to be a longshot.

Why not have everything feed a generator when power's present, have the generator feed the UPS and then the UPS feed the load? That way you don't worry about inconsistencies due to incompatibility with respect to power.

[Cap1_apc]

Hi,

I would say you've got yourself quite an "interesting" set up there.

To support that amount of equipment at 120v, you would most likely need two UPS's. The problem is, you would also need a substantial amp feed (30amps) to support the load, most likely not going to be available from a car.

As for the future solar panel, I'm not sure on what kind of system you are planning on installing, but if the solar panel output is 120v, it should work in theory. Typically though, a solar panel system will have its own battery banks to charge and use.

How long do you need the UPS to support the load in times of no power source?

[Anonymous user]

Interesting is a good way to put it. It is actually turning out to be harder than first imagined. Anyway, what would you (anyone) expect the potential output from a vehicle alternator? We need as much power as possible for as long as possible. Realistically we would only need to battery backup a load of about 1500-2500 watts for as long as possible.

[Anonymous user · Accepted solution]

A heavy duty alternator in a truck/van would be somewhere around 120amp, that is only about 1650 watts at full output, plus the vehicle would need some of this to run. Moreover, the alternator would not produce full output with the engine idling, you would have to have a way to hold the RPMs up.

Solar panels are 12 volt and are usually around 120 watt per panel and would be used to keep a battery bank charged. A 4kw solar system would be in the neighborhood of $40,000 and require a lot of area for the PV panels.

A gas powered generator sounds like the best solution in your case.

Stew.