ProMariner Battery Isolator User Manual

Owners Manual & Installation Guide for ProMariner Battery Isolators

Please read this manual for proper installation and operation of this device.

For all product, installation or service questions please call ProMariner direct at:

1-800-824-0524 Eastern Time 9:00am – 5:00pm

ProMariner Marine Battery Isolators are rated for use with negative ground alternators that range from 10
amps to 130 amps output, and will operate on 6, 12, 24, 32, 36 volt negative ground systems. They are
solid-state devices which allow electrical current to flow in one direction only. This allows one or two
alternators to be connected to multiple battery banks without fear of fully charged batteries discharging
into undercharged batteries.

Note:

ProMariner Battery Isolators are not recommended for use with any self energizing
style alternator. ProMariner isolators are to only be used with negative ground systems.

For Proper Installation:

Mounting:

Mount the unit in a well ventilated location as near to the alternator a possible. Do not mount the unit on an
engine or in proximity to an exhaust manifold.

Wiring:

The battery cable should be sized in accordance with the engine manufactures recommendations. Ring
terminal connectors sized in accordance with wire size (see table for wire sizes). 5/16” rings are
recommended. Fuses must
from the battery isolator. See chart below for fuse sizes. Refer to the American Boat and Yacht Council’s
recommendations for additional information on the installation of battery isolators.

be used 7” from the alternator and 7” from the batteries on all leads coming

Wire Size Table

Alternator Output

40 #8 awg #6 awg
50 #6 awg #4 awg
70 #6 awg #2 awg
100 #4 awg #2 awg

Amps 10ft 20ft

Fuse Size Table

Batt. Isolator Amps Fuse (please see below diagram for placement)

70 100amp
100 160amp

Frequently Asked Questions:

1) QUESTION: What is an isolator used for?

ANSWER: They are solid state devices which allow electrical current to flow in one directly only. This allows one or

two alternators to be connected to multiple battery banks without fear of fully charged batteries discharging into
undercharged batteries.

2) QUESTION: How do I know which isolator I need?

ANSWER: It all depends on the number of alternators you have, the amperage output of the alternator(s), and the
number of batteries that you are wiring to. Note: Professional Mariner Isolators are not recommended for use with
any self energizing style alternator.

3) QUESTION: How do I wire up the isolator?

ANSWER: The isolator is wired between the alternator and the batteries. One or two alternator input terminals

connect from the alternators to either two or three output terminals connected to batteries.

4) QUESTION: There is no output voltage on my isolator?

ANSWER: Check to see if the isolator is working with a digital multi-meter set on “DIODE CHECK” mode. Put the

red lead on the alternator input terminal and the black lead on one of the battery output terminals…..you should get
a reading around .4 on most meters. Then reverse the leads and you should get a reading of infinity. Perform this
procedure from all of your alternator input terminals to all of your battery output terminals. If you get a different
reading with the red lead on a battery terminal then the isolator is defective.

We are committed to customer satisfaction and value your business. If at any time you experience a
problem with your new ProMariner battery Isolator, simply visit www.promariner.com

or call us at

1-800-824-0524 for technical support.