Elecric 12v fridge

[Robbo]

13 minutes ago, colmac said:

Many thanks to all for the replies to my post. Proves the value of this forum. Hate to show my ignorance but can someone explain what an " equalisation charge " is please.The only problem with this forum is it really exposes huge gaps in my knowledge of things electrical. Thank you.

http://batteryuniversity.com/learn/article/equalizing_charge

Stationary batteries are almost exclusively lead acid and some maintenance is required, one of which is equalizing charge. Applying a periodic equalizing charge brings all cells to similar levels by increasing the voltage to 2.50V/cell, or 10 percent higher than the recommended charge voltage. 

An equalizing charge is nothing more than a deliberate overcharge to remove sulfate crystals that build up on the plates over time. Left unchecked, sulfation can reduce the overall capacity of the battery and render the battery unserviceable in extreme cases. An equalizing charge also reverses acid stratification, a condition where acid concentration is greater at the bottom of the battery than at the top.
 

Edited March 26, 2018 by Robbo

[dor]

The manual for my fridge with GD30FDC compressor is self selecting on the voltage:

Quote

From the value of the applied voltage, the electronic driver
automatically decides the rated voltage range of the supply.
Three possible ranges are considered:
12 to 14V: actual voltage is below 17V
24 to 28V: actual voltage is within 17 and 33V
36 to 42V: actual voltage is within 33 and 42.4V

It also states: "The compressor can be powered by a variable DC source as,
for instance, a photovoltaic panel, in which the output voltage
strongly depends on the intensity of sunlight radiation. In
these special cases the driver should be programmed with rated,
minimum and maximum voltages. These values should be
within the allowable DC voltage power supply (10 V to 42.4V)."

It would appear that it will happily run on its 12V setting at up to 17V.

 

[colmac]

15 hours ago, Robbo said:

http://batteryuniversity.com/learn/article/equalizing_charge

Stationary batteries are almost exclusively lead acid and some maintenance is required, one of which is equalizing charge. Applying a periodic equalizing charge brings all cells to similar levels by increasing the voltage to 2.50V/cell, or 10 percent higher than the recommended charge voltage. 

An equalizing charge is nothing more than a deliberate overcharge to remove sulfate crystals that build up on the plates over time. Left unchecked, sulfation can reduce the overall capacity of the battery and render the battery unserviceable in extreme cases. An equalizing charge also reverses acid stratification, a condition where acid concentration is greater at the bottom of the battery than at the top.
 

Many thanks for this, I even understood it !

 

[WotEver]

6 minutes ago, colmac said:

Many thanks for this, I even understood it !

If you want something a bit more in depth you might want to read this: