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Discussion Starter #1
Hello...!!!

New owner, new member here. Been lurking here a few days mostly on performance subjects.

In particular for this post, I plan to "upgrade" the sound system. The factory system is among, if not the best I've heard, as far as factory systems go that is... but still subpar by my standards.

I have a few threads regarding max continuous power available to the 12V system. 22.5 or even 30 amps will just not get it for my tastes... and I don't need any jargon about music being dynamic power. WRMS power is WRMS power. Though technically the term is jargon in itself, it does represent a method of "averaging" the dynamic power of a suond system. A max of 30 amps at 12V equates to 360 WRMS, period. I'm designing my sound system as efficient in the watts to decibels department as I possibly can. But currently estimating I'll need more than 360 WRMS.

The discussion in the other threads I've read seem mostly based on what amounts to replacing the factory 12V battery with one having greater surge capacity (such as an Optima or Kinetic battery). FWIW, that only works for the short term...

I travel in my profession, i.e. 500+ miles one way to get to the job sites. Once there, I only commute until the job is done... then perhaps another 500+ miles back to the homestead. While I'll likely not be jamming at max decibels the entire trip, I can foresee discharging (to a degree) any battery on the long hauls. While heat is the number one destructive factor of electronics, undervoltage exacerbates the effect. Ultimately, I need to find a way to get more juice...!!!

So getting down to the nitty gritty, it currently amounts I cannot install (though I've not investigated the possibility of adding) an alternator with greater output... cuz' the Z has none. As I understand it, the 12V charging system relies on a DC-to-DC converter (i.e. volts to volts) and is the limiting factor. However, can easily be likened to and underrated alternator on non-hybrid cars.

So what do we do in that case? Generally two options or a combo thereof, and that is to get a beefier alternator, and/or install a second, or third (or fourth in extreme cases, given there's enough room... :)) BTW, I have a full size chevy express conversion with a 11,000 WRMS A/V system and a single underrated 300A alternator, but two to five Kinetic 3800 batteries depending on whether I'm in competition mode or not :) ... so I do know what I'm talking about here.

Anyway, I'm currently seeking information on the DC2DC converter. Exactly where is it located? (pic's???) Exactly what is it called by Honda? ...or its part number? How was the 30A figure determined? Has anyone considered, looked into, or actually paralleled two or more of them?
 

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The DC converter is in the boot and is part of the Power Control Unit. If you want to look into more detail there is a lot of work on You tube on the Insight on the Electrics.
Page 12-50 in the service manual will also give you a lot of info.
And welcome to the club! :)
 

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Discussion Starter #3
Thanks for the info, Dwight...!!!

Currently working on obtaining a service manual (SM). HelmInc only has 2011 and 2011-12 versions. Can't find a 2013 version. Even local Honda dealership doesn't have one. Does anyone have a link?

If the dc-dc converter is in the battery unit, to mod' it makes for a potentially expensive voiding of warranty (~US$2,800 retail) :eek:

Being I am currently without an SM, can someone check if there is a full-time, full voltage on the connector pinout? ..and wire size? ...pin number/image? ...etc.?

If there is, could possibly use an outboard dc-dc converter...
 

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I made those measurements. The recommendation of 22.5 amps is based on the assumption that you do not want to make any mods to the electrical system whatsoever. If you want more power whenever you drop the bass, you can consider adding either capacitors or a battery.

Tell you what, if I have time this weekend, I'll re-do the measurements, noting voltage this time. I suspect that the battery is hovering around 11.8 volts (and decreasing as I run the experiment), and the DC/DC converter puts out 13.85 volts (that is the voltage at which a fully-charged car battery is, with no load).
 

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Discussion Starter #5
I made those measurements. The recommendation of 22.5 amps is based on the assumption that you do not want to make any mods to the electrical system whatsoever. If you want more power whenever you drop the bass, you can consider adding either capacitors or a battery.

Tell you what, if I have time this weekend, I'll re-do the measurements, noting voltage this time. I suspect that the battery is hovering around 11.8 volts (and decreasing as I run the experiment), and the DC/DC converter puts out 13.85 volts (that is the voltage at which a fully-charged car battery is, with no load).
Paraphrasing, you are saying the max standard 12V equipment load is 7.5A? That's what it amounts to for a 30A max converter output less a 7.5A running load and 22.5A available for whatever is added... right?

The question is, how did you determine the 30A rating for the converter?

Regarding battery voltage, if the 12V system voltage hovers around 11.8 while engine is running and the 12V system loaded, to me that says the converter is not sufficiently keeping the 12V battery charged. A conventional 12V lead-acid battery fully charged should be 12.6V (6 cells at 2.1V each). At 11.7V a conventional lead-acid battery is considered 0% charged. Granted those numbers are for open-circuit voltage, but they should hold true for "closed" circuit voltage if the battery's charge is being maintained. That's why I'm questioning the 30A rating. It may only be 30A for a short period and diminish over time in use.. For high-powered aftermarket equipment, what we need to know is the max continuous rating if we are comparing to our equipment's Wrms rating.

FWIW, for the most part there will be little noticeable difference on standard 12V equipment. However, the 12V battery will experience a shortened MTBF compared to what it would be if charge was maintained continuously. Honda's engineers likely made a trade-off by shortening the potential 12V battery life to extend the IMA battery life. Given the cost difference, I can see that being considered a reasonable compromise since the 12V battery under nominal conditions is not being used to start the engine, which is the leading cause of failure for old-school vehicles.

While cap's will help with the dynamic surge demand necessary for accurate music reproduction, they do nothing to improve continuous load ratings. Adding one or more batteries serve to improve both surge and continuous current capacity, but the power consumed still has to be replenished by some means or we just experience a shortened life cycle of multiple batteries... :cry:

So my current focus is tapping the power of the IMA battery... or more accurately, its charging system. The power has to travel between the electric motor and battery by some physical means (TTBOMK, Honda is not using wireless power technology to date :rolleyes:). Given the 12V charging system originates in the IMA battery unit, that accounts for one wire. What are the others? I have to assume there is more than one :)

PS: 13.8V is battery charger open-circuit voltage (actually 13.2 - 14.4V). 14.4 at the battery terminals is considered gassing voltage, an explosive condition.
 

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Someone tested the DC/DC converter to 75 Amps. They were using their car as a backup generator when their power went out. The worst-case load on the system I can think of was 50.8 Amps (base load + HID headlights + fog lights + blower on full tilt + defrosters). The 22.5 Amp figure is, again, conservative, risk-adverse, no mod required.

I should also clarify that the engine was not running when I was taking the measurements, so it is 11.8 volts loaded, not open-circuit. Everything was being powered off the battery. However, when the IMA DC/DC converter is active (even in auto-stop), voltage was pretty much constant at 13.8 volts (according to an OBD II reader I used).

Lastly, the IMA battery is 100.8 VDC, so you will need an additional DC/DC converter. I do not know where you can tap off of it. They are the wires shrouded in orange. I would love to experiment and help you out, but this car is my only car, so I would not want to mess with anything which is related to the powerplant (the hybrid system being in the group).
 

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Discussion Starter #7
Someone tested the DC/DC converter to 75 Amps. The worst-case load on the system I can think of was 50.8 Amps (base load + HID headlights + fog lights + blower on full tilt + defrosters). The 22.5 Amp figure is, again, conservative.

I should also clarify that the engine was not running when I was taking the measurements. Everything was being powered off the battery. However, when the IMA DC/DC converter is active (even in auto-stop), voltage was pretty much constant at 13.8 volts.

Lastly, the IMA battery is 100.8 VDC, so you will need an additional DC/DC converter. I do not know where you can tap off of it.
Thanks for the clarification. Someone probably threw 30A out there because the 7-speaker system is advertised as a 360W system. Divided by 12V is 30A... but I've not seen any claims that the 360W rating is in Wrms units. It could just as easily be 360W max. With audio component ratings, more often than not, a lack of "rms" suffix usually indicates its a max or peak rating. Regardless, if replacing the amplification portion of the system, whatever it draws will add to the availabe current.

The 2013 has a 144VDC IMA battery. And I realize I'll need another dc-dc converter. Already have one in mind. Just have to confirm it's DC input voltage rating. Saw it rated up to 144VDC on a vendor's site, but not on the manufacturer's site. FWIW, I have three Kinetic 3800's sitting in my basement on a trickle charger. Will likely use at least one.

Now where can the 144VDC system be tapped???
 

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I have a 2011, so I can't help you there. :( Remember the orange-shrouded cabling I mentioned in my previous post? I will have to say NOT there, because that is most likely three-phase AC, and could be cut off when in auto-stop. What DC/DC converter do you have picked out?

Regarding the 360-watt rating of the factory amplifier, I agree that it is most likely peak rating. :D I tried to blast some Lindsey Stirling, but couldn't get more than 5 Amps continuous.
 

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Apparently you didn't check occupation in my profile. :eyebrows: In the automotive arena, 144VDC is high voltage. In the electrical arena, 600V and under is considered low voltage. Of course that figure will vary by electrician or electrically related professionals, but 600V is the value established under the National Electrical Code. In my professional occupation I work with systems in the tens of thousands volts (not to mention nuclear reactors rated in megawatts :)). But technically speaking, I don't actually work on anything energized over 50 volts. The main issue is that I'm trained in avoiding serious mistakes and their consequences.

3Ø isn't a problem. How do you think alternators work? What a lot of non-electrical persons do not understand is the voltage between any two energized wires of a 3Ø electrical source is still 1Ø. The 120/240V electrical services in residences all start out at the power plants as 3Ø and only branched off as 1Ø for local services.

So we could take three 1Ø inverter/chargers and connect them to "rotated" pairs of the three wires... tripling the output of just one. What would need "engineered" is compatibility of the inverter/chargers for variable input voltage and current. And don't forget that I will have an additional battery or two, so my purpose isn't necessarily to provide a continuous power but to beef up the 12V charging system.

The DC-DC converter I had in mind:

Converter/Charger PowerMax 120 VAC/96-144 VDC Input to 13.4V 100A Output, 3 Stage Charger

...but since you brought up 3Ø, I'm going to research the feasibility... especially the cost.
 

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Discussion Starter #10
Regarding my research into a 3Ø method, haven't found anything more economically viable than using a DC-DC converter/charger. I have contacted a couple manufacturers, regarding the use of their AC-DC converter/chargers simply by cutting off the AC plug and connecting to DC, and awaiting a reply.

In the meantime, I got curious enough about tapping the 144V system that I opened up my IMA battery pack and found two terminals to which I can connect. Being the process was exploratory, I didn't take pictures. However, I have yet to reassemble because 1) it was getting dark, and 2) I want to purchase some wire, make the connections, and bring out the wires before I close it up, so I don't have to reopen. I'll try to take pictures on reassembly...
 

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It's possible there could be an issue with IMA system having a "mysterious" power drain on the battery. Will there be errors in calculating the SOC? Will it throw a code if it detects higher than expected current from the battery? I too have thought about powering a device off of the high voltage system, but in my case it would require a complely different charging/regen profile, so that will probably never go anywhere unless someone figures out how to hack the IMA ECU...
 

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It's possible there could be an issue with IMA system having a "mysterious" power drain on the battery.
Yeah, maybe the entire 12-volt system is a "mystery" power drain. I'm sure Honda did not make such an elementary mistake. It'd be interesting to know what voltage the exposed terminals provide.
 

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Discussion Starter #14
@cyeung

No imminent plans on circuit protection at this point, but there will be circuit protection at some point. I will fit it in as parts are determined. At this point, I'm thinking any fuse(s) or circuit breaker will be outside the battery case for ease of access.

@ITEM9

Yes, that is entirely possible... and I am currently researching it as best I can with limited information.

What is SOC?

My current thinking is that basic design principles are in play. The first is, no one has truly put a smart battery on the consumer market. By that I mean, no one puts sensor electronics in the battery cells themselves. All monitoring is done by sensors external to the cells, either mechanically attached, such as temperature sensors, or in-circuit, such as voltage and current measuring devices. Going on this premise, there must be a point between the battery terminals and these external sensors where current is not monitored. However, voltage and temperature will be affected even by pre-sensor current draw.

With incomplete engineering data, there'll be a point where I'll likely just have to have a leap of faith or abort :eek:
 

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SOC = State Of Charge. Remember: The goal of circuit protection is to protect the wiring so it does not melt, set adjacent items alight, etc. Tip: Locate the protection as close as practicable to the source. You will need a fuse rated for a minimum of 144 VDC. I emphasize VDC because something of this voltage will require a non-standard fuse, for arc containment reasons. There is NO zero-crossing in DC, ya'know?

Whether to take the leap of faith or abort really hinges on two things, in my opinion: Whether you have another ride and whether you can shoulder the cost to restore to normal in the event things do not work out. I'm not trying to scare you -- I just want you to go into this with your eyes wide open.
 

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Discussion Starter #16
SOC = State Of Charge.
Thanks!!!

Remember: The goal of circuit protection is to protect the wiring so it does not melt, set adjacent items alight, etc. Tip: Locate the protection as close as practicable to the source. You will need a fuse rated for a minimum of 144 VDC. I emphasize VDC because something of this voltage will require a non-standard fuse, for arc containment reasons. There is NO zero-crossing in DC, ya'know?
Umm... preaching to the choir :)

Whether to take the leap of faith or abort really hinges on two things, in my opinion: Whether you have another ride and whether you can shoulder the cost to restore to normal in the event things do not work out. I'm not trying to scare you -- I just want you to go into this with your eyes wide open.
1) I do have another ride.

2) In most all of my customizations, I attempt to minimize costs to restore appearance... followed by performance, if at all possible.


Nonetheless, I appreciate the peer check :)

Will update as I proceed (or not)...
 

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Progress report. Made the taps. Pictures follow. They were taken on reassembly. However, I'm presenting them here in dis-assembly order...

***Disregard the red loom tubing until the last picture.***

First up is a block diagram of the IMA. Note it is from the 2011-2012 service manual, but I have assumed the only difference is the battery voltage. AFAICT, placement of modules and devices in the 2013 IMA battery are not the same.



Here we see the top of the IMA battery case. Remove bolts indicated.







I forgot to indicate removal of four torx-head machine screws from top of cover plate, and two push-pin fasteners near rear bottom of cover (i.e. the cover's profile is L-shaped turned on its right side and as if looking at it from the passenger side)

Below we see the actual top cover of the IMA battery unit...



Here I show measuring 150VDC with both module switch and key ON. The reading was 0VDC before turning the key ON, and after turning the key OFF, the voltage gradually dropped back to 0VDC after a couple minutes.

The indicated negative terminal is where I made the negative tap.



Here I show the MCM flipped up to expose the otherwise obscured contactor and current sensor. *NOTE* if you follow this procedure, there is no need to remove the MCM fasteners and flip it up. **NOTE** you will be tempted to set fasteners on flat spot to left, and perhaps some to right side (not pictured). I advise against it, especially during wire and loom tubing manipulation. The fasteners can very easily be knocked down in between the case and body... like I did :( . I managed fish all but one push-pin fastener, and it was no fun, let me tell you. Suggest putting the fasteners in a small container and setting them outside the car.

The indicated positive terminal is where I made the positive tap.



And finally, here I show the routing of wires in loom tubing...



Regarding the red-colored tubing... I wanted to use orange, but I couldn't find any locally. I had a choice between red and blue... or order 100' of orange and wait for it. The latter was out of the question, because tomorrow I have a 10AM that's approx. 90 miles away... :)
 

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Discussion Starter #18
UPDATE

Got replies from two manufacturers of converters...

Iota Engineering

Me: I read over on Cloud Electric's website that the DLS-75 can be used as a DC-DC converter simply by cutting off the plug and connecting the black wire to the negative and white wire to the positive. Is this true? If yes, is it also true of the other 12VDC output DLS models? Also, is the any reduction to the published output rating?

Iota Engineering: It doesn’t matter if you connect the black or white to positive or negative, there is not polarity. This is true of only the units with the fins on the side of the chassis (68 series), not the series M converters. 130VDC in will give you the 13.6VDC output, it will adjust as you adjust the input.

****

PowerMax

Me: Are any of your converters capable of DC input. My project requires conversion of 144Vdc nominal input to a typical 12V battery powered system. Output current capacity needs to be not less than 75A.

PowerMax: Yes the PowerMax units can also do DC to DC and within your requirements of 144Vdc to 12V at 75A. The DC will have to be connected by removing the AC socket [plug] and wiring this into you DC source and the unit is grounded on both AC and DC.

****

The suitable Iota models (75A and 90A output) cost more than PowerMax's units (up to 100A output). I found the PowerMax PM3-100 priced at $143.50 here and ordered one...
 

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This thread is interesting on several levels...for anyone that wants a larger 12v source. Thank you very much on the current info, and I look forward to later installments!
 

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Can I ask why you chose to wire it like that? Seems like it would be easier to tap the neg and pos points and connect them to a external terminal located on the ima case it self. Making it easier for a "quick" removal if needed? I guess if you took it in for warranty you would want to just remove everything anyways I guess, idk
 
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