Precision Circuits LiFePO4 Battery Isolation Manager

Under normal charging conditions, the BIM will connect for 15 minutes every 35 minutes. That means that the BIM will connect for 15 minutes, disconnect for 20 minutes, and repeat this cycle until the coach battery is charged.

If the coach battery resting voltage exceeds 13.4V than the BIM will disconnect. A resting voltage greater than 13.4V indicates a fully charged battery. Note that “resting voltage” means that no current is flowing to the coach battery.

The BIM will disconnect if the alternator voltage exceeds 14.4V. This protects the coach battery from over charging.

The BIM will disconnect if the voltage difference between the alternator and the coach battery is less than 0.1V. If the voltage difference is too low, then there is a negligible charging current, and no need to connect to the coach battery

The BIM will disconnect if the alternator voltage drops below 13.3V. If the alternator voltage is too low, than it cannot adequately charge the coach battery, so there is no reason to connect.

Made in the USA.

1. 160Amp & 225amp continuous models available 

2. Runs cooler using less power

A. Draws no current in On or Off State

B. Excellent for Solar Panel Use

3. Microprocessor Based

A. Monitors battery state over longer periods of time

B. Not simply voltage dependent

4. Approved for Battery Compartments

A. Ignition Proof, SAE J1171

B. Waterproof, IEC 60529, IP66 IP67, ASTM B 117 96 Hours Salt Spray

5. Chargers

A. Lithium Coach Battery from Alternator

B. Lead Acid Chassis Battery from Coach Charger

6. Isolates Batteries to prevent discharging or overcharging of Batteries

7. Prevents

A. Equalization cycles from Damaging Chassis Battery

B. Annoying Clicking of Isolator Relay

C. Overcharging of Coach Battery during long drives

D, Overcharging of Coach Battery during long stays

8. Provides Emergency Start with Dash Switch. Optional power connection for existing applications, and ground connection to allow Emergency Start of either battery

9. Weighs under 1 pound

Relay Contacts- 

  • 160 Amps Continuous

Wire Size-

  • 2/0

, Amps Continuous-

  • 225A

Amps Intermittent, 30 Seconds

  • 1200A

Maximum Dimensions (WxHxD)- 3" x 5 1/4" x 2"

Mounting Holes- Three 3/16" Holes


Coach or Chassis Battery-  5/16" Ring Terminal

Input Terminals- #10 Ring Terminal


Waterproof- IEC 60529, IP66 IP67, ASTM B 117 96 hours Salt Spray

Ignition Proof- SAE J1171

Coil Volts DC- 

  • Minimum- 9.0VDC
  • Typical- 12.0VDC
  • Maximum- 16.0VDC

Coil Amps DC-

  • Typical- 10 Amps
  • Maximum- 0.25 sec max internally protected

Ambient Temperature- -40°C - 60°C

Switch Life- 50,000 Cycles