Eric Hysteric wrote:
I bought in Poland (my mother is living there) for 25 $ an used "Schaudt" transformer with IUoU charging method. It's better for my battery than the 40 years old transformer i have now.
I had only 1 battery for the engine and the home.
I bought an in Europe very popular Victron Cyrix-ct 12/24V-120A battery disconnect relais and a second battery.
I've done a bit of research, resulting in evidence your purchases are good.
IUoU charging is three-stage charging and a DIN-designation. DIN-designation is a long time body of standards that are widely recognized and referenced.
DIN is a German language acronym, translated into English as German Institute for Standardization. In this respect, it is similar to ANSI and other organizations. DIN is also part of ISO, with DIN-designations probably subsumed into ISO standards.
Because your charger's design and operation is based on a recognized independent standard, it gets a 'plus mark' in terms of my personal preferences. (I'm not aware of any similar standard for 'three-stage charging' in the United States and would need to do some digging to see what the ISO standard is, if one exists.)
The Victron Cyrix-ct 12/24V-120A is similar to the Blue Sea Systems m-ACR in function and operation. ACR means Automatic Charging Relay, which is a term I prefer over battery disconnect. (Battery disconnect is a loose term applied to a wide range of products with significant differences in function and operation ... for example, antiquated 'battery isolators' are sometimes called battery disconnects.)
The Cyrix-ct is better than the m-ACR in terms of max amp rating. (Cyrix-st is rated 120 amps while m-ACR is 65 amps.)
m-ACR is suitable for small to medium outboard motors and engines with (in modern terms) relatively small alternators. The OEM alternator in older motorhomes was/is 65 amps so an m-ACR could be used there. The m-ACR is a 'no-go' for older motorhomes with larger retrofitted or aftermarket alternators, as well as most newer vehicles with larger OEM alternators.
I consider the Blue Sea Systems m-ACR a
marginal option for older motorhomes because it's amp rating is too close (actually identical) to OEM alternator output. (As a general design criteria, an automatic charging relay's rating should be at least ten amps higher than the alternator's output.)
Blue Sea Systems does offer ACRs with higher ratings but they are significantly more expensive and include additional features that aren't relevant to my applications. The Cyrix-ct does one job and presumably does it well, while probably costing less than the Blue Sea Systems alternatives. (K.I.S.S.)
All in all, the Cyrix-ct appears to be a better option than the m-ACR for our older motorhomes.
So, Eric, I'd appreciate knowing what you paid for your Cyrix-ct. (DM or EU is fine, I can convert to USD.)
Likewise, I'd appreciate a post-installation report on how it works for you.
