EMS Ultimate Battery Backer JR/S/Z

Tower Stock# LXAFN0  •  Manufacturer Stock# EMO0013
EMS Ultimate Battery Backer JR/S/Z (large view)
Notes from our tech department:
This is the Ultimate Battery Backer from Electronic Model Systems.
This is a device which switches between main and auxiliary battery packs
depending on the voltage difference between them.


Works with 4 or 5 Cell NiCD packs.
Works with 6Volt Gel-Cell or Lead Acid batteries.
Universal connector works with Hitech, Futaba, and Z connectors.
Main and backup batteries must be the same number of cells and the
same voltage.
Capacity of the two packs is not required to be the same.
Simple wiring and installation
Optional remote backup indication
Optional inflight backup indication
60 Amp MOSFET devices used as battery switches.
MOSFET device ON resistance of 0.018 ohm or less for minimum voltage
Lightweight device


One Battery Backer with pre-installed conenctors
One Instruction sheet


Two receiver packs


Length: 39mm (1.54")
Width: 37mm (1.46")
Height: 19mm (0.75")
Weight (without conenctors): 0.6 oz
Voltage switch: When main pack falls 1.2 volts below auxiliary pack


If both packs fail, the backer will switch to whatever pack has
higher voltage.

cmc 12/31/01

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