Saturday, January 15, 2011


The standard converter that Lazy Daze uses is the Parallax (formerly Magnetek) 7345 model, which like many switching DC converters on the market, is not a good battery charger since it will only deliver a maximum voltage of 13.8 VDC. Due to the constant voltage of 13.8, it also means it's not a great converter to leave plugged in for extended periods (weeks on end) as it will boil the electrolyte of your batteries causing you to check/fill the reservoirs more often. Never-the-less, this converter works fine for people that don't go camping off-grid on a regular basis or don't leave their RV plugged in 24/7 for long periods of time.

If you find yourself having to add water to your house batteries fairly often, you might want to consider upgrading your converter/charger to a 3-stage charger model, which will be much more gentle on your batteries. There are many to choose from and most are a drop-in replacement for the stock 7345.

The most popular brands of replacement units are the Progressive Dynamics (PD) Intelipower units. PD makes a number of models with various amperage output, ranging from the stock 45 amp replacement units on up to 70 amps. If you decide to go with a higher output unit, be sure to upgrade the in-line fuse to accommodate the higher power. PD units include what is called the Charge Wizard, which constantly monitors the state of the batteries and adjusts the charge as needed. It delivers 13.6 VDC normal mode, 13.2 VDC standby, and has an equalization cycle that provides 14.4 volts for 15 minutes every 21 hours while in standby mode. Since it's a true 3-stage charger, it will charge much more quickly due to the higher voltage capability and you can expect to fully charge a single, size 24, 85 AH battery in just 4 to 6 hours vs. 16 to 36 hours with the 7345.

The larger Progressive Dynamic's PD9270, rated at 70-amps, has been used successfully by several LD'ers to replace 6300/7400 series converters. It includes the Charge Wizard 4-stage charger control and is the largest converter that will fit into the same place as the original converter. You can download the PDI 9200 Series Owner's Manual. You should consider replacing the wiring between the converter and the batteries with heavier gauge wire to handle the increased current.

Other brands include Iota and WFCO who also make drop-in replacements.

The actual replacement is reasonably easy. There are two major steps - replacing the lower converter/charger unit and replacing the 12-Volt fuse panel (the 12-volt panel is included, but it is not necessary to replace; it does offer two more fused circuit positions, however). If you do it wire-by-wire it's hard to go wrong, although in true Lazy Daze fashion, the wire lengths are minimal and it's a bit of a struggle to get the wire end to the new terminal.

The replacement 12-volt panel has red LED's below each fuse to show which fuse has blown. but only if there is a circuit connected with a path to ground. A mis-wire might prevent the light from coming on, or if there is another fuse also open in that circuit.

While you're at it, you might want to consider installing a "whole-house" surge protector. While you have the converter compartment open, it's easy to wire in the surge protector so that it protects both shore power and generator power.

See also Converter Wire Size

Contributors: WxToad

Revised 30 Apr 2011

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