Picture of West Mountain Radio ISOpwr+ (Plus) Auxiliary Battery Isolator
West Mountain Radio ISOpwr+ (Plus) Auxiliary Battery Isolator
  • $119.99
  • Out of stock
  • SKU: ISOpwr-Plus

West Mountain Radio ISOpwr+ (Plus) Auxiliary Battery Isolator

Equipment powered from the auxiliary battery never drains the vehicle's battery. When the vehicle's engine runs, the auxiliary battery is charged. If the engine is not running, the auxiliary battery is disconnected from system. Read Full Description
Availability: Out of stock
SKU: ISOpwr-Plus
  • Isolates and charges a 12 Volt auxiliary battery to run mobile radio and other 12 Volt portable equipment.
  • Ideal for mobile radio command stations for ARES, RACES, FEMA, and for a VHF/UHF Contest Rovers, moderately powered ham equipment, a re-charging station for electric model airplanes, boats and cars, and for RV's and campers.
  • Charging from vehicle starts when the car is running and the alternator is maintaining the car battery over 13.5 volts.
  • Charging from vehicle stops when the alternator is off and the car's battery has fallen below 12.6 volts.
  • All solid state. FET switch. No relays. Handles up to 40 amperes. Input fuse 40A.
  • Works safely with all types of 12-volt lead-acid batteries, Flooded Lead Acid, Gelled & AGM.
  • May be used without a battery to automatically turn a radio on whenever the car is running. The radio will turn off with a small delay after the car is stopped.

New Improvements

  • PWRguard output shut-off when voltage is out of range
  • USB port for setting operating thresholds and for monitoring
  • Smaller and lighter weight enclosure
  • Dimensions: 4.5" W x 3.4" L x 1.4" H


  • Operating Voltage: 20V maximum
  • Quiescent Current: Less than 5mA
  • Maximum Current: 40A
  • Voltage Drop: 0.25V at 1A, diode drop
  • Series Resistance: 0.01 ohms maximum
  • Switch Time-Constant: 5 seconds
  • Turn ON Threshold: 13.3 (+/- 0.1)V
  • Turn OFF Threshold: 12.6 (+/- 0.1)V
  • Green LED: Indicates the ISOpwr output is ON
  • Dimensions: 4.5" W x 3.4" L x 1.4" H
  • Weight: 0.35 lbs
  • Enclosure: Aluminum case


  • ISOpwr+ Unit
  • Battery Fuse & Terminal Kit
  • (4) Rubber Feet
  • Owner's Manual
Customer Reviews
Random radio shutdowns By
I share many concerns of the previous reviewer.  I own both an ISOPRW and an ISOPWR+.  Random radio restarts also.  Used utility to adjust low voltage settings with no change.  Support was helpful with suggestions, but ISOPWR+ is now out of warranty and random radio restarts have resumed.  I have swapped out the ISOPWR+ for my older ISOPWR and all is fine.  I'll check out the fuse connection the previous reviewer mentioned.  Thanks for the suggestion.
Was this review helpful? Yes No (5/0)
A Lot of money. Flimsy and not well supported By
I purchased this unit, and external LiFePO4 battery, cables, a special USB cable to analyze this unit's log data, and an inline PowerPole voltmeter.  When all connected, I discovered my radio was shutting off at odd times.  The unit instructions describe situations like this, like when the vehicle battery runs too high or too low in voltage.  So I decided to run the WMRDIAGNOSTICS utility.  The section in the manual, by the way, does a terrible job of telling you how to use this utility, how to read the log data, and how to change the default parameters.  As an aside to this review, here is how you use the utility:
1) download the WMRDIAGNOSTICS utility
2) install it on a laptop.
3) run a USB micro B cable to the ISOpwr+.
4) run the utility.
5) check the box to save the log data.  Then, double-click on the COM port row that lists the ISOpwr+
5) click once inside the black box that appears.
6) press S

Well, after spending a total of $236 for all the things I needed, I finally figured out why my radio is dropping power periodically.  It's not that my car hit the High Trip or the Low Trip value; there is a loose connection around the 40 amp fuse holder on the vehicle connector.  Jiggle it a bit and the power comes on.  Jiggle it more and it cuts out.  The fuse is fine.  This was a huge disappointment and a big time-sink.  :-(
Was this review helpful? Yes No (12/4)
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