Bulbs are just variable resistors as their resistance changes with filament temperature. The way we are talking is correct. The way you are interpreting it is incorrect.


You have described two bulbs in series as have we. Remember that bulb ratings are in watts. A LOWER WATT bulb has a HIGHER RESISTANCE. Two 150W bulbs in series is has the same RESISTANCE as a single 75W bulb.


Again, I'm not sure where you're going with the 1V comments. A healthy NiMH cell that has been discharged to 1V at 0.2C or lower has ZERO available or usable capacity. It is empty. If the cell suffers from voltage depression, it has more capacity that it can deliver at 0.8V; however, it can only do so at lower current because the chemical reactions are much slower. Once the capacity is consumed at this lower level, the chemistry is "reset". When the cell is charged after consuming this voltage depressed capacity, the proper chemistry is restored with essentially all of the usable capacity now available at 1.2V instead of a mix of 1.2V and 0.8V.


The discharges are doing the above on a cell level 120 cells at a time to varying degrees in accordance with the voltage depression or lack thereof present in any cells.


The first discharge restores the cells with the worst voltage depression. Subsequent discharges to lower voltages reclaim capacity from increasingly healthy cells.


Overcharging as I've described is a non-issue. NiMH is EXTREMELY overcharge tolerant. To repeat, ANY time you have discharged a pack at low current to 120V or less, you should input 10,400mAh to ensure that all cells are at true 100% SoC.


Main leads are always zero or near zero when connected to the car (small voltage on car side of connection is possible). If you cut a circuit, you have a break in the circuit. It is cut at a location of 0V potential from one side to the other, so it's not possible to measure a voltage across the open circuit.


The main leads are relay-isolated.


Master switch breaks the circuit between subpacks. With master switch off, there is no external voltage measureable anywhere on the pack.


The main terminals only have PACK voltage when the car closes the 12V relay after determining the HV battery should be in the circuit. If the car is running, but the pack is isolated, you get voltage at the main terminals proportional to engine rpm.


With the pack master ON, you get voltage between one of the main leads and the battery side of the relay.


Refer to HA's installation instructions to find these connections.

 

How do you get the large orange connector near the bottom left to let go?

It may have been some aberration but between main negative and what appears to be a nearby gnd wire had some single digit volts, which appeared to discharge (in asymptomatic fashion) as I measured it. Not sure if it's the 12v circuit vs the 144 or what. smaller orange wire comes from inside battery pack and is bolted just link a ground, to the side of the BCU. I didn't open the 12V circuit ...probably should have...

I think I was conflating resistance with current flow.

 

I have an HCH1 pack, but I haven't looked at it in months. Please pick an image from this page and let me know what you mean:


https://hybridautomotive.com/pages/install-c1

 

Is that link unlisted? I trolled the whole **** site.

I think its #25 I saw that it had to come off of the little metal mounting tab, but even putting it on just enough for leverage (dont want to pull the wires on the back connector OUT of the connector.) Its the one hanging lowest in 28A. HA says its a crush and release but it looks like one where you insert the screw driver and lift up the tab to release. I'll look again to be sure though. He's probably done one or two more than I have

 

It's a link on the Product Guides page:


https://hybridautomotive.com/pages/prolong-user-guides


That connector is very stiff. It's a two handed job where you have to hold both sides.

 

This was during earlier construction, its all built now. Please let me know if you see anything incorrect. I'll be **** sure I have the line to the batt polarized correctly!
Ended up being scared romex would be too inflexible so I cut up old computer power cables instead.


I am considering doing everything but that connector, and partially removing the batt so I have better access... according to glove manufacturers I have medium hands but its really hard to get them both in there LOL

 

I had a hard time following the wiring. The ammeter must be in series, i.e., if you disconnect one of the ammeter leads, you have an open circuit and can't charge or discharge until the ammeter lead is reconnected. You may have it this way, but I can't tell for certain.

Do you have diodes wired into the PSU output? If not, I recommend you do so.

Alternatively, you need to make sure the PSU is ENERGIZED with AC power BEFORE connecting or disconnecting to the pack. You can also simulate this with the master switch, e.g.,




To start charge:
Master switch off
PSU connected
PSU energized and voltage confirmed
Master switch on
Pack voltage and 350mAcurrent flow confirmed


Top stop charge:
Master switch off
PSU de-energized
PSU disconnected


Diodes make it easier as you never have to worry about the order.


These PSU are not designed to work with inductive loads - only resistive loads - a battery is both. Subjecting them to the backflow from a battery can damage them.

 

 

Ok, batt is out and now next to my contraption in the video.
Threw the main breaker and hmm still 0volts. Do I need to put 12v someplace to open the relay?

I'll get back on my desktop and read further in the install guide on HA for clues

EDIT: for some reason the post quoted was the latest one the mobile site was loading. Reading that now

 

If it were me I would wire a small known resistance into the circuit and measure the voltage across it. A 5W 1 Ohm power resistor might be a good choice. Maybe if I had a high quality Fluke ammeter it would be OK to leave it in the circuit all the time. Mine are cheap Harbor Freight devices and I don't trust those not to fail.

Several posts above you noted that it is important to charge slowly and for a long time to get all of the cells up to 100% charge. Just to make it clear for anybody who might not be up on the battery chemistry, what is happening is that once a cell is fully charged it goes into an overcharging state where it generates gas. The batteries contain a catalyst which recombines the gas into water, releasing heat as it does so. If the current rate is slow enough the catalyst can handle all the gas produced and nothing bad happens, other than the batteries heating up a bit. If the current rate is too high the rate at which gas is generated will also go up. If that rate is too high either the catalyst falls behind and the pressure builds up, venting the cell, or the catalyst keeps up but the heat generated is very high. Either is bad for the cell. Something similar happens when the cells are discharging. Which is why near either charge extreme it is very important to keep the current low.

Also, as you have said before, but it bears repeating, it is important not to try to start the car with the battery discharged. If the controller does not figure out in time that the IMA is empty, and it usually won't, it will try to pull a large current out of the pack and this is a bad idea with most of the cells way outside their normal working state. I suspect it also isn't a great idea to start the car when the battery has just finished a 30 hour charge. Let it rest a while so that any free gas in the cells can recombine, and the resting voltage can drop back into a more normal range.