Our Parallax Power Center, Series 7300 (specifically 7355), has a converter that failed
during the two year warranty period of our 2007 23’ Safari and was replaced with another Parallax converter by our dealer last September. Last week the replaced converter also failed.
Based on good reports
from others here on the forums, we decided to call Randy
and order the Xantrex XADC 60A Converter/Charger (Hard wire)
Unlike our two-stage Parallax converter, the Xantrex’s three-stage charging process results in batteries charging faster and more effectively. Xantrex’s 3-Stage White Paper (see link
on BestConverter.com) describes the stages:
The first stage, bulk
, is a constant current mode that replaces 80% of the battery’s capacity quickly. The charger applies its maximum output current as the battery voltage rises. When the battery voltage reaches a predetermined absorption voltage, operation switches to the second stage.
The second stage, absorption
, is a constant voltage mode and replaces the remaining 20% capacity. The charger voltage is held steady while the current falls as the battery approaches full charge.
In the third stage, float
, the charger voltage is lowered and held constant at a safe value of 13.5 volts DC, which prevents the battery from being overcharged, while allowing the charger to supply enough current to maintain the battery at a full state of charge.
The Xantrex converter arrived quickly via FedEx from BestConverter.com. Randy steered me to the Parallax 7300 Upgrade Procedure link on their website. This procedure, “Parallax 7355 Converter Replacement with Xantrex XADC-60
”, was written by Ernie Hensley of Spokane Valley, WA, who has a 28’ 2005 Airstream Safari. His procedure has detailed instructions and photos, which greatly assisted me. He also kindly answered my questions via email. I downloaded Ernie’s photos into our laptop MacBook Pro, to have nearby as I followed his procedure.
This and following posts will describe and illustrate how I replaced our Parallax converter with the Xantrex. It is not intended to tell you how you should replace yours. It is posted to show what worked for me, which may be helpful to others.
First I disconnected the 30-amp shore power. Then I turned the Battery Disconnect Switch to “Store” and used a voltmeter to ensure that no battery power was reaching the converter. Note, as pointed out by Ernie, it may be safer to disconnect the batteries at the battery terminals, but again, this is what worked for me. Our power center is located in the middle of our trailer under the double wardrobe closet.