48051 - Diode Battery Isolators Series

Series: Diode Battery Isolators
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Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

For vehicles with two batteries, these devices electrically isolate the batteries to prevent the battery with the higher charge from draining into that with the lower charge. In addition, both batteries can be charged simultaneously from one source.

The amp rating of each item is the maximum alternator rating. Most alternators on new vehicles have an integral electronic voltage regulator that requires the use of the 4-stud battery isolator. The small 4th stud is for connection to a circuit switched by the ignition switch. The newer alternators were first introduced by Delco and are therefore sometimes called 'Delcotron-type alternators'. A 4-stud battery isolator can be used with older pattern alternators (in this case the 4th stud will remain unconnected), but a 3-stud battery isolator cannot be used with the Delcotron-type alternator.

Features
  • General purpose Battery Isolators for 12-36V DC negative ground systems
  • Electronic components are embedded to give excellent protection from adverse conditions, such as contamination and vibration
  • Integral heat sink provides efficient heat dissipation

Per Leg Ratings
Battery isolators have a 'per leg' rating which indicates the maximum current it can deliver to either battery. All Littelfuse Cole Hersee brand battery isolators have a per leg rating equal to half the alternator rating. For example, the 48051 with a rating of 75A has a per leg rating of 37.5A per leg.

Ordering Information

Part Number Amp Notes
48051 75 A Used to isolate medical equipment batteries from vehicle batteries. With Schottky diode, to comply with Federal Spec. KKK-A-1822B
48070 70 A Use with alternators that do not have integral electronic voltage regulator
48090 90 A Use with alternators that do not have integral electronic voltage regulator
48092 90 A For use with Delcotron-type alternators
48120 140 A Use with alternators that do not have integral electronic voltage regulator
48122 140 A For use with Delcotron-type alternators
48160 200 A Use with alternators that do not have integral electronic voltage regulator
48161 250 A Used to isolate medical equipment batteries from vehicle batteries. With Schottky diode, to comply with Federal Spec. KKK-A-1822B
48162 200 A For use with Delcotron-type alternators
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Product Literature


Property (Mouseover for details) Value
Current Rating (Continuous) in Amps 75
Ingress Protection Fully Sealed
Output Terminals Two 1/4 Studs
Housing Blue Heatsink
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