Why does the Emriver use a 12-volt pump?

[gravelbar]

For two reasons: Safety, and to provide for field use. Using a 12-
volt system as opposed to, say a house current-powered submersible
pump, means that there is very little chance of getting dangerous
voltage/current into the Emriver system. Since the system is both wet
and made of aluminum, this is important!

By the way, you should *always* use a GFCI outlet or a portable GFCI
unit to plug your power supply into, just to add another layer of
safety. In July of 2008, we began to provide these to Emriver users
in case their labs didn't have GFCI outlets (which, of course, they
should).

Using a 12-volt system also allows use of a small deep-cycle battery
to power the Emriver model. One of my favorite places to set up an
Emriver is on a gravel bar next to a real river--you can point to the
features in the real river and relate them to their counterparts in
the Emriver. Very powerful for teaching.

Steve