Going on a year and a half now now and hasn’t skipped a beat.
Alternator Voltage Booster
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Diode Functionality Question Answered: See Edit Below
HKB MK3 Users: Could you check the MK3 fuse with a multimeter- while the fuse is plugged in and take a reading across the two poles on top of the fuse and let me know what you find. How many mA are you reading? If you pull the fuse and take an Ohm reading- what value to you read?
I was looking for a parasitic draw in my engine bay fuse box- testing each fuse for current draw. When I came to the MK3 ( which resides in the ALT-S fuse location) I found it was "live" drawing about 15 mA. It's not a lot of drain but that circuit should be off when the key is off. Inserting a 7.5A fuse in that spot- there is 0 mA draw. I reached out to HKB earlier in the week, haven't heard anything back yet.
Thanks
Edit: 3.10.23 (MK3 looks like a fuse but isnt- Dont test a Diode on DC-V DC-Auto)
I've been using a generally accepted (automotive) practice to test for parasitic drain by measuring voltage drop in a circuit across the poles on top of a fuse and that's what I got hung up on that I couldn't understand why I was getting a voltage reading in key off state from my MK3 voltage booster (which is a diode with a "fuse-like" internal reset feature if the circuit exceeds 7.5A).
I've been looking at the testing process assuming the MK3 voltage booster (a diode) to measure the same way as a fuse. I was wrong. Depending bias of the diode (forward bias or reverse bias) you'll get an erroneous voltage reading (when using DC-V) giving the false impression of mA drop.
So, since we are testing a Diode ( and not a fuse)- after some digging I learned how to test a diode using "Diode Mode" on my DDM- if you dont have the Diode setting on your multimeter you can Resistance test on Ohm setting.
My MK3 seems to be working properly and tested ok.
In Diode Mode: 0.525V and .OL in the opposite configuration
In Resistance Mode: 4.05 oHm, .OL in the opposite configuration
Here is a good tutorial on testing Diodes
www.fluke.com
My DDM- I am using a INNOVA 3320
HKB MK3 Users: Could you check the MK3 fuse with a multimeter- while the fuse is plugged in and take a reading across the two poles on top of the fuse and let me know what you find. How many mA are you reading? If you pull the fuse and take an Ohm reading- what value to you read?
I was looking for a parasitic draw in my engine bay fuse box- testing each fuse for current draw. When I came to the MK3 ( which resides in the ALT-S fuse location) I found it was "live" drawing about 15 mA. It's not a lot of drain but that circuit should be off when the key is off. Inserting a 7.5A fuse in that spot- there is 0 mA draw. I reached out to HKB earlier in the week, haven't heard anything back yet.
Thanks
Edit: 3.10.23 (MK3 looks like a fuse but isnt- Dont test a Diode on DC-V DC-Auto)
I've been using a generally accepted (automotive) practice to test for parasitic drain by measuring voltage drop in a circuit across the poles on top of a fuse and that's what I got hung up on that I couldn't understand why I was getting a voltage reading in key off state from my MK3 voltage booster (which is a diode with a "fuse-like" internal reset feature if the circuit exceeds 7.5A).
I've been looking at the testing process assuming the MK3 voltage booster (a diode) to measure the same way as a fuse. I was wrong. Depending bias of the diode (forward bias or reverse bias) you'll get an erroneous voltage reading (when using DC-V) giving the false impression of mA drop.
So, since we are testing a Diode ( and not a fuse)- after some digging I learned how to test a diode using "Diode Mode" on my DDM- if you dont have the Diode setting on your multimeter you can Resistance test on Ohm setting.
My MK3 seems to be working properly and tested ok.
In Diode Mode: 0.525V and .OL in the opposite configuration
In Resistance Mode: 4.05 oHm, .OL in the opposite configuration
Here is a good tutorial on testing Diodes
How to Test Diodes with a Digital Multimeter | Fluke
Learn how to test diodes with a digital multimeter.
www.fluke.com
My DDM- I am using a INNOVA 3320
Last edited:
From the description not sure you are using the amp meter correctly.
Amp meters are inserted between components, not around components.
Amp meters have low resistance so can appear like a short and change the circuit behavior.
Like this
Fuse socket -------- Fuse -------- amp meter ----- Fuse socket
Not like this
Fuse socket ---|---- Fuse ---------|-- Fuse socket
__ ____ ___ ____ |--- amp meter ---|
Im using a Multimeter in DC auto-mode so it reports whatever amount if current that's coming into it. Placing the test leads directly on top of the fuse to check for current flow. Checking Ohms just pulled the fuse and tested the two blades of the fuse on the bench. HKB read 4.5 Ohm's - standard fuse read 0.0.
Is that using it wrong?
Is that using it wrong?
Not correct. Depending on the amp meter, say fuse has significantly lower resistance than meter, most all the current will flow through fuse and meter will only read the small amount going through it. Now if the meter resistance is way lower than the fuse it will read most of current but some will still go through fuse and not be measured.
Huh - ok
Well thank you but are we splitting hairs? Obviously I’m getting current flow through the MK3 diode fuse when there should be none - it’s measurable on my multimeter-however it may not be reading the total amount of current throughput as you indicated.
Never the less- with standard fuse inserted there is no current flowing in key off state- and with the MK3 it’s allowing current flow which brings me back to the original ask in in my post- to know if others with the MK3 have the same readings.
Well thank you but are we splitting hairs? Obviously I’m getting current flow through the MK3 diode fuse when there should be none - it’s measurable on my multimeter-however it may not be reading the total amount of current throughput as you indicated.
Never the less- with standard fuse inserted there is no current flowing in key off state- and with the MK3 it’s allowing current flow which brings me back to the original ask in in my post- to know if others with the MK3 have the same readings.
The mk3 itself cannot create any current or create any parasitic draw just by itself.... something would have to be feeding it power.
if you wanted to see how much current that circuit uses, you could pull the mk3 and then use the probes of your multi meter into the terminals of alt-s. Setting your multi meter to the appropriate setting you can use it to measure how much current is flowing across the terminals of the slot, which would be the same current that would flow across anything in that slot.
I could imagine a situation in which there is a capacitor that is bleeding back in the direction that the diode would normally block. With the regular fuse in place, that capacitor would bleed off VERY quickly, but with that diode in place, that capacitor might bleed off VERY slowly or not at all. Thus, putting your meter across the terminals with mk3 in place would give current flow when the ignition is fully off, as the multi meter is bypassing the diode and allowing current flow.
if you wanted to see how much current that circuit uses, you could pull the mk3 and then use the probes of your multi meter into the terminals of alt-s. Setting your multi meter to the appropriate setting you can use it to measure how much current is flowing across the terminals of the slot, which would be the same current that would flow across anything in that slot.
I could imagine a situation in which there is a capacitor that is bleeding back in the direction that the diode would normally block. With the regular fuse in place, that capacitor would bleed off VERY quickly, but with that diode in place, that capacitor might bleed off VERY slowly or not at all. Thus, putting your meter across the terminals with mk3 in place would give current flow when the ignition is fully off, as the multi meter is bypassing the diode and allowing current flow.
You may also have current flow through the standard fuse, if the meter's resistance is high enough you would not see it.
In general since you are not using the amp meter the way it is designed to be used, you really don't have good data, and other folks readings would be all over the map depending on design of their meter.
If you think you are on to something, go for it.
To determine wheather current is flowing in a circuit you should measure for voltage in MILLIVOLTS across the fuse test points. Voltage seen there will indicate CURRENT is flowing through the fuse. If current is indicated, the fuse can then be pulled and the current measured by directly probing the fuse socket with an AMPMETER.
I got it figured out and edited my original post up in #82. Where I went wrong is that I didn't consider I was testing a Diode and expecting it to report the same values like a fuse when testing across the poles. Two very different test procedures with different results. Thanks guys.
Question: Can I use a Mk3 with a flooded battery?
Background: I have a single 27 flooded duralast Gold battery that serves the truck. The alternator (indicated by scangage) generally puts out about 14.2 on startup and recedes to about 13.6 or so when warm. During high load (wipers/idle/AC&blower on/lights on), it sometimes drops to low low 13's, sometimes into the high 12's. The alternator is a newish denso and the condition of the connections are clean/tight throughout. I did the big 3 minus the firewall because of perceptible NVH, so Big 2. The truck also has a 600W amplifier and a 300 W powered sub, all by Rockford Fosgate so real power.
I get the Mk3 may provide a 0.5V boost, but will the flooded battery not do well with that?
Background: I have a single 27 flooded duralast Gold battery that serves the truck. The alternator (indicated by scangage) generally puts out about 14.2 on startup and recedes to about 13.6 or so when warm. During high load (wipers/idle/AC&blower on/lights on), it sometimes drops to low low 13's, sometimes into the high 12's. The alternator is a newish denso and the condition of the connections are clean/tight throughout. I did the big 3 minus the firewall because of perceptible NVH, so Big 2. The truck also has a 600W amplifier and a 300 W powered sub, all by Rockford Fosgate so real power.
I get the Mk3 may provide a 0.5V boost, but will the flooded battery not do well with that?
thanks for this im going to do something similar in my 80
I'm running dual AGM and as you can expect they aren't charging well, or lasting long. I've read through the above thread and my understanding is there are three options to up our alternator output:
Thanks in advance!
- HKB offerings that has been out of stock forever
- Wire a diode to the fuse
- Use Little Diode 02400113XP but this eliminates the capabilities of the fuse
Thanks in advance!
Until you figure out your voltage booster, having a good float charger (ctek for example) on hand to top up your batteries monthly should help with battery longevity.
Isolating your start battery from your house battery should also help- that is being able to disconnect the house battery and only charge from your alternator when you’re adventuring and using it. Your charging system will thank you with longer alternator life.
I’ve got the HKB booster and it’s worked well enough for the past few years. But I run a single 92aH AGM dual purpose starter/deep cycle battery- not duals. I don’t drive my Cruiser daily so it gets a float charge every few weeks to keep the battery happy.
Isolating your start battery from your house battery should also help- that is being able to disconnect the house battery and only charge from your alternator when you’re adventuring and using it. Your charging system will thank you with longer alternator life.
I’ve got the HKB booster and it’s worked well enough for the past few years. But I run a single 92aH AGM dual purpose starter/deep cycle battery- not duals. I don’t drive my Cruiser daily so it gets a float charge every few weeks to keep the battery happy.
You could easily just put a diode and make a pigtail on the alternator sensor wire easy to undo and keep your charge fuse. I’ve got one made my M2K.inc I sent them what alternator I’m using 390A alternator and battery combo(AGM deepcycle). And I am now getting ~14.8vdc at idle.
Just a quick heads-up that the HKB MK3 is finally back in stock.
7.5A MK3 Mini Blade (Electronic fuse version) | HKB Electronics
The Alternator Voltage Booster was the first of its type on the market and is the only unit available that was has been purpose built for alternator voltage boosting.
www.hkbelect.com
I have used the MK3 mini-blade for a couple years while running a single AGM battery, and it has worked great. During the hottest couple months of summer, I reinstall the factor fuse out of an abundance caution (for the welfare of my battery) since I spend a lot of time in slow, hot metro traffic. During this period I top up the battery every couple weeks during the night.
I installed a MK3 today and got the battery symbol on the dash. I'm totally lost. (running single AGM)
Installed backwards
