On Mon, 23 Jul 2007 14:52:51 GMT, "Karl Townsend"
wrote:

I burned the bearings out on my drive turbine for the traveling irrigator.
To get by, I removed the turbine completely and I'm pulling hose in with the
tractor PTO.

I LEARNED SOMETHING! The turbine takes its power out of the water pressure.
Its reducing pressure to the sprinkler from 115 PSI to 100 PSI. And the gun
works WAY better at the higher pressure.

The power from the turbine is dinky. You twist it by hand to start it when
it stalls. I'm going to guess 10 ft lbs. It runs at maybe 500 RPM. There's
then a gear train that reduces the speed by maybe 500:1 to give high torque
to the bull gear driving the reel. This assembly pulls in a 3" water hose at
50 feet per hour.

I'm wondering if a DC motor and deep cycle batteries would do this job. This
thing needs to be super reliable, it runs more than 120 hours a week. Am I
within the power range of a DC motor setup? I'd need at least 8 run hours
between recharging. What would be the best unit in terms of efficiency?

FWIW, I could lay a 110 volt wire in the fence line where the traveler hooks
up. Line loss would be terrible because it would be over 1/4 mile long. But
maybe it could run a 12 volt charger. I couldn't get to all the spots this
way.

I won't be trying this in the middle of this drought. I'd build it this
winter.

Karl

What is your flow rate in gallons per minute, Karl?