PROBLEM WITH REDARC DC to DC

POWER PLAY

Imagine a night of celebration with friends at Big Red and a little too much use of the 240V Cooking appliances from the inverter. Suddenly, there is absolutely no power.

This was the scene last Friday night for a couple at the base of Big Red. They drove back to Birdsville expecting the Redarc BCDC to charge… but alas it didnt.. and can’t.

In the morning in the full Birdsville sun, they expected the BCDC solar input to charge the batteries…. but alas it didn’t… and can’t.

The Redarc BCDC was not faulty. It just cant operate without a 12V power supply. When the battery is dead, it will not work as intended.

SOLUTION

A Victron Smart Solar controller will operate and charge a flat battery without needing 12V at the battery. Victron’s clever design bleeds power from the solar panel input to power up the bluetooth communication channel and the on-board microprocessor. Had a victron solar controller been installed, then the BCDC would have been activated once the battery got a little bit of power in it and would have charged on the drive back from Big Red. From then on, full recovery would have followed.

TRAP with BATTERY POWERED MICROPROCESSORS

There are other products that have the same problem. The Enerdrive EPro Combi Inverter/Charger was prone to this design fault. Most kit assembled Lithium Battery power packs also rely on 12V power to function. If you wish to avoid being stranded, having an independent power source, like the Victron Smart Solar is essential.

FLAT BATTERIES: SAFIERY LITHIUM 2 x 125Ah
– FULL PERFECT RECOVERY

The reason why we know about this Redarc embassasment is because the user had Safiery Lithium batteries in their CUB Camper. Two of them in fact, in parallel. The batteries were so discharged, even the Bluetooth Communication was out of service; so the battery voltage was less than 8V.

The couple devised a great plan of using the DC output from a borrowed generator. After guiding them on removing the megafuse to the inverter (source of power drain), their plan worked perfectly and within 30 minutes the bluetooth communication came up and batteries were once again ready to take power. If a friendly generator had not been available, it would have been a very sad trip through the Simpson. Of course, getting help in Birdsville was the alternative plan.

INVERTER DRAINING YOUR BATTERIES

The purist reading this will point the finger at the Inverter as the root cause of this couple’s problem. They are, of course correct. However there is the “double trouble” question of Inverters with a high “standby” current, draing your precious battery power.

Here is a comparison of popular brands and their published power drain when on standby. Victron’s Smart Inverters use HALF the power of the other’s published data.

In 24 Hours, an inverter drawing 1.2A accidentally left on, will drain 28.8Ah out of the batteries!

INSTALLING LOW VOLTAGE CUTOUTS to SAVE YOUR BATTERIES

Installing low-voltage cutouts is often mandatory with brands susceptable to these design limitations. With Victron Inverters, the low voltage cutout is built into the Inverter. It is set from your smartphone and is even intelligent enough to adapt the cut-out voltage based on the dynamic current draw. This means it will cut out earlier if a heavy current is drainging the battery compared to a light one. This is very useful when recovering from a deep discharge.