Originally Posted by
drivesafe
Hi Bill, if you are fitting an electric winch then I recommend you fit a USI-160.
Even if you are only planning to use the winch infrequently, there are advantages to both having two batteries supplying the winch while it is in use and to using the USI-160.
Best practice winching is to have your motor on high idle and winch for 60 seconds, then rest for 90 seconds and then repeat for as long as you need.
The short winch period means the winch shouldn't get too hot while in use and the rest period both allows the winch to cool a bit between uses and to allow the battery, or batteries, to recharge.
By allowing the battery time to recharge, between uses, the voltage going to the winch, while in use, will be higher. Higher voltage at the winch means the winch will not have to be used as hard to achieve the same amount of work.
This reduces the heating of the winch and ware on the winch.
By adding a second battery to a winch setup, firstly the voltage at the winch is going to be even higher. The load the winch is pulling is going to be spread over two batteries, so less stress on the cranking battery.
While in the rest cycle, you will replace more of the used battery capacity and again, this means higher voltages at the winch while it's in use.
Instead of fitting a USI-160 isolator, you could link the batteries either with a marine battery switch or a heavy duty solenoid, controlled by a switch in the cab.
The problem with using either a marine battery switch or a heavy duty solenoid is that if when you have finished winching, if you forget to turn the marine battery switch or a heavy duty solenoid off, and you go off camping, you could end up with two flat batteries.
The USI stands for Ultra Smart Isolator and here are a few reasons why.
Under normal operation, the USI-160 would be in the recommended SHARED Mode, and this has a minimum pre-set Cut-Out ( turn off ) voltage of 12.0v but when you select WINCH Mode, the USI-160 automatically resets the Cut-Out voltage down to 10.0V.
The 10.0v voltage allows for both batteries to be used while winching, but if you are not taking care while winching and you operate your winch down to a stall situation and don't stop winching, the USI-160 will disconnect the auxiliary battery so that if you damage the cranking battery, you still have the auxiliary battery as an emergency backup.
Next, if once you have finished your winch operations but forget to switch the USI-160 back to normal operations, if you turn your motor off, 5 minutes after your motor is turned off, the USI-160 automatically resets the Cut-Out voltage back up to 12.0v, removing any risk of you flattening both batteries while camping.
Hope this answers your questions.