Installation Manual


Introduction
The Magnum Energy Class T Fuse Block is designed to provide code compliant over-current protection for
mobile applications. It protects the battery bank, inverter and cables from damage caused by short circuits
and overloads. It uses a fast acting, current limiting class T fuse cartridge which provides instantaneous
protection in the event of a short circuit but also employs a time delay to allow momentary current surges
common in inverter applications. Available in 300 and 400 amp models. Magnum fuse blocks are ideal in
mobile applications where over-current protection is required for high current components such as inverters
and chargers. A rugged injection molded polycarbonate base and thermoformed ABS cover provides
durability, easy installation, and good looks all in a compact, cost effective package.
Fuse Selection
Fuse size is determined based upon the size of the conductor between the battery and the load. Factors such
as the length of the cable between battery and load and wire type of the conductor as well as conductor
temperature rating all affect the conductor’s current carrying capability.
The following information provides general guidelines in fuse selection.
Inverter Conductor Gauge Current Capacity* Recommended Fuse Rating
ME 3112 4/0 AWG 360 400
ME 2012 3/0 AWG 310 300
*Based on 75 degrees Celsius cable rating in free air @ 85 degrees Celsius
Installation
The fuse should be installed between the battery and the load in the ungrounded conductor. This is
normally the positive or red color-coded conductor. Install the fuse block in an easily accessible location.
For code compliance, locate the fuse within 18” of the battery with at leas 6” of clearance form the other
equipment. Attach the fuse block securely to a solid mounting surface using appropriately sized hardware.
Connections to the fuse block require ring terminals. Make the cable connections to the fuse block first,
then to the battery and finally the inverter. Always check cables for correct polarity before making final
connections.
Place the ring terminal on the end of the cable over the stud on the fuse block. Install the flat washer, the
lock washer and the nut in that order. Do not put any washers between the ring terminal and the fuse, as this
will cause hardware to 250 inch-pounds (21ft. lbs.) Threads are specially lubricated to assist in future
disassembly.
Warning: Failure to comply with torque specifications may result in damage and
premature failure of the product. Failures caused by not adhering to the proper torque
specifications are not covered by warranty.
For more information contact:
1111 80
th
Street SW Suite 250, Everett, WA 98203
Phone: [phone] Fax: [phone]