Anyone have have experience with the HKB Electronics MK4 Adjustable Regulator? I want to run other batteries and the existing charging voltage is barely enough to charge a factory lead acid. I have two AGMs I've been holding back.
Adjustable Voltage Regulator (1 Viewer)
- Thread starter Bunga
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Taco2Cruiser
Crazy American Off Road
Had mine since ‘16 (in my ‘11). Works perfectly and actually keeps my Northstar AGM at 100%. Really couldn’t ask for more.
Keep in mind though, that we have temperature controlled voltage regulators (not the real terms, but it help get the point across to who ever will read this). So sometimes it’s hard to get a proper reading of output from a snapshot reading.
Keep in mind though, that we have temperature controlled voltage regulators (not the real terms, but it help get the point across to who ever will read this). So sometimes it’s hard to get a proper reading of output from a snapshot reading.
Markuson
SILVER Star
Yes. Highly recommended.
I switched to their user-variable unit and even happier. It lets you tweak the voltage rather than their normal set resistor...and it’s kept my damaged (by Toyota) AGMs alive and kicking despite 4 years of more heavier use than anyone I know. HKB for the win.
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CharlieS
GOLD Star
@Markuson - can you share any additional information about the user variable unit - how it works, the range of adjustment, what output you are getting, etc. I put the non-adjustable HKB diode in and have been happy with it, but I'm still putting out at the low end of the voltage Odyssey recommends for their AGM. The auxilliary is fine, since the BCDC steps up the voltage, but I've been curious if the adjustable HKB unit can be used to up the output by another couple of tenths of a volt while charging the primary battery.
RobW0
GOLD Star
Do these work on the newer 200's? Was thinking I had seen in one of these threads that they don't.
Markuson
SILVER Star
Can’t go into detail at the moment, but it lets you bump as high as a full volt.
.2, .4, .6, .8 and 1.
You can just make one. Instructions around here somewhere. Takes about 1/2 hour. Requires an add a fuse and a diode .
Builds - The Guzzler - 2009 LX570
How has your AHC held up with the mods and that many miles? Also, what’s your oil of choice and interval? Thanks! Beautiful LX!
forum.ih8mud.com
Here's the post
We've run them in dozens and dozens of Cruisers. My own personal 100/200, the Expedition Overland fleet and many customer setups running AGM. Definitely recommend them.
If I understand correctly, these drop the voltage level as sensed by the alternator so that it thinks it is outputting less than it actually is. As a result the alternator will compensate with a higher voltage output to bring the measured voltage up to what it thinks it should be. Net result is the alternator outputs a higher voltage.
So given this there is no way to increase the voltage to the aux battery while leaving the starting battery alone? For that I would need a more sophisticated voltage regulator, something like the Redarc BCDC?
So given this there is no way to increase the voltage to the aux battery while leaving the starting battery alone? For that I would need a more sophisticated voltage regulator, something like the Redarc BCDC?
CharlieS
GOLD Star
I don't know that the BCDC is the only way, but I do know that is what the BCDC does. I have the 1225 in my LC.
A single charger cannot properly detect and tender two batteries at two different states of charge. The first battery to be fully charged will be what the charging source detects. Thus whichever battery at a lower state of charge will be never be fully charged.
Modern alternator regulators are more similar to intelligent chargers as they don't produce excess current that the circuit or battery doesn't need. These modern alternators have charging profiles and temperature compensations specific to batt types. Vice old alternators (~pre early 2000s) that were more constant voltage and produced excess power where one could setup a dual battery without a secondary charger like a BCDC.
Smart alternators exist as they are more gentle on batteries promoting longer usable life (remember days of adding water to batteries?). Primarily, they are more efficient reducing parasitic draws on the engine, increasing fuel efficiency.
To answer your question, yes, probably can get away with this hack and may potentially work without a BCDC. At a cost to battery life and fuel efficiency.
