Monday, April 6, 2015

Powering Emriver Geomodels with batteries

Students experimenting with an Emriver Em2 geomodel.
There's nothing quite as cool as running an Emriver model next to an actual river! It's a fantastic way to teach fluvial geomorphology.

Our Em2 and Em3 models are designed for portability, and you can use them just about anywhere. For field sessions or spots without easy access to wall current (or "mains power" in the UK), you can use a 12-volt battery.

While we supply a battery power hook-up kit, we do not supply batteries. They are best bought locally. Here are a few tips on finding the right battery:

1. Make sure it's a "deep cycle" battery. Car and motorcycle batteries won't work. They are not designed to be deeply discharged, and they will be damaged if they are.

2. Make sure it's a sealed battery that can be tipped, even used upside down, without spilling acid. These batteries are designated "SLA" for "sealed lead-acid." Another designation to look for is "UB" for "universal battery." These are very commonly used for computer backup systems (they're inside that big black UPS box) and to power alarm systems during power outages.

3. Get a battery with at least 12 amp-hours of capacity; this will sometimes be abbreviated as "12ah."  The Em2/Em3 pump uses only about one Amp of power. A good 12 Amp-hour battery should power it for at least four hours. If you want to know more about this, there are many sources on the web, and here's a detailed one.

The photo below shows a good choice, a UB12120, or "universal battery" 12-volts, 12 Amp-hours. This battery will weigh only about seven pounds and be 6 x 3 x 3 inches in size. It's very compact and easy to manage. These can be bought locally and online.

Get a charger from whoever sells you the battery, and you're ready for the field! You don't need a large automotive-style charger. Here's a small one we like at LRRD.

A UB12120 universal battery.

Emriver battery adapter and extension cord.


1 comment:

Mike said...

This a very good blog. What you guys did there was so very awesome.