Batteries, Alternator, Winching, Check Gauges

[Andyba20]

I’ll admit I don’t think I really understand the relationship between the batteries, alternator, battery temp sensor, pcm and the check gauges light. Yesterday I was doing a heavy pull with my winch, on 30 seconds off 30 seconds, and my check gauges light came on. The volt gauge was below 8, and I waited a min and it ever came back up. I assumed I’d blown my 200 amp fuse between the alternator and battery. I checked the fuse and it was fine, looked at the gauge again and it was back to charging (so 3-4 mins between check gauge warning and normal charging again). Every component in the charging system is in new/better than stock condition. All positive/ground cables are new, all terminals new, @W-T mod with parallel grounds, 4 gauge b+ cable, 200 amp fuse, 2 new batteries 3 months old and tested. Nations 180 alternator.  Grid heaters were not cycling. Ambient temps around 45*. So was the pcm giving a command not the alternator not to charge for a minute, or was the heavy pull getting the batteries so low it just didn’t register? I was watching the gauge closely and when it dropped below 8 it seems to do it instantly which is why I thought I’d blown the fuse.  Again, it was a heavy pull but with my ****** blocks I had a 4:1 mechanical advantage that put me well within the specs of the winches rating. 

[Tractorman]

15 minutes ago, Andyba20 said:

So was the pcm giving a command not the alternator not to charge for a minute, or was the heavy pull getting the batteries so low it just didn’t register?

 

First, I commend you on having a proper setup for winching, and for you giving a great description of your symptoms!

 

When batteries and a charging system are tested to the limit (winching will do that), then the smallest inefficiencies of the electrical system can come into play.  To help with figuring this out, more information is needed - mainly two factors.  Was the engine at idle?  Do you know the maximum current rating of the winch?

 

Other things that could cause the symptoms:

 

*  The batteries (even though they are new) need to be at a fully charged capacity just prior to winching.

*  The alternator could be at fault (charging at reduced capacity)  Alternator output can easily be checked at a good auto / electric shop

*  The heavy cable and cable connections (even though they are new and routed properly) could have one poor connection. 

 

Think of it this way - every battery cable has four connections.  Example (using the battery crossover cable):  passenger side battery to clamp, clamp to passenger side cable wire,  cable wire to driver side clamp, and finally clamp to driver side battery. So, one wire - four connections.  Multiply that by number of cables used means a heck of a lot of connections.  Something that I always remind myself - an electrical system can only perform at the level of its worst connection.   It only takes one poor connection to dramatically reduce performance - especially under heavy electrical load.

 

I recommend hooking up your winch to a heavy continuous load.  With a helper operating the winch, use your voltmeter to check voltage at each battery and relevant connection points while under load. 

 

- John

 

[Andyba20]

Thanks for the good ideas @Tractorman

 

To answer your questions, this is an old Ramsey worm gear winch that has been well taken care of and is pretty much unstoppable. The max current rating is 370 amps. I was at idle, but the Nations 180 at idle has an output of 120 amps, it maxes at 180 amps at 1,800 rpm. The voltage is always steady at 14.2, after a 30 second pull the voltage gauge would dip to 10-11 volts, I would stop and after the 30 second recovery it would climb back to 14.2. Everything worked fine except for this 3-4 min pause where it appeared the alternator wasn’t giving any output.  It kicked back in and went to 14.2 and the rest of the pull went fine. 

[Tractorman]

The dash voltage gauge is fine to use for general reference, but it is not a reliable diagnostic tool.  A voltage reading at each battery will tell the story.  When winching current well exceeds charging current for 30 seconds at a time doesn't mean the alternator has quit charging (indicated by dash voltmeter).  A voltmeter at the batteries will immediately show rising voltage when the winch is turned off if the alternator is charging.  The dash voltmeter may / will not.

 

- John

 

 

[Mopar1973Man]

Be aware that if the battery voltage shows 12.00 volts it will show normal on the volt gauge. After the voltage falls to 11.99 volts it will slam the needle down to 8 Volts and throw the  light and chime. Once the voltage rises back above 11.99 volts to 12.00 volts it will turn off the check gauge light and then show normal voltage. The only reason I know this is my USB charge point shows actual battery voltage with the key on. I can see actual voltage numbers on my USB port. 

 

@Tractorman is correct your best off with a Digital Volt Meter. You will be able to check each battery for its charging voltage. I've found several trucks that show correct voltage on the gauge but like the passenger battery is low like 12.3 volts and the driver side battery is 14.8 volts. This shows the battery terminals and/or cables are bad. 

[Andyba20]

4 hours ago, Tractorman said:

The dash voltage gauge is fine to use for general reference, but it is not a reliable diagnostic tool

10-4, I wasn’t so much using it for accuracy but as a consistent reference as I was doing the pull. The needle would slowly dip during the pull and then slow rise during recovery. This happened for about 6 on/off 30 second cycles before the check gauge light came on and the needle went all the way to 8, then there was no slow rise which made made assume it wasn’t charging. I did go ahead and start monitoring voltage via the adrenaline monitor (iPhone) after that. So am I hearing you and @Mopar1973Man say the pcm cannot or does not command the alternator to stop charging under certain conditions? 

[Tractorman]

50 minutes ago, Andyba20 said:

So am I hearing you and @Mopar1973Man say the pcm cannot or does not command the alternator to stop charging under certain conditions? 

 

I don't know.  The only way to really know is by having a multi-meter connected to one of the batteries to measure voltage while the winch is under a load as you described earlier.  This is one thing that I don't really care for regarding computers - they can be programmed in many ways to perform certain tasks under varying conditions.  If you aren't privy to the program's instructions, you are not going to know what will happen under certain conditions. 

 

It could be that the alternator is still charging, but the voltmeter in the dash has been instructed to turn off when battery voltage drops to a certain threshold.  Just don't know.  Reading battery voltage at either battery with a multi-meter won't lie, it will tell you if the alternator is charging immediately when you stop the winch operation.

 

- John

[Andyba20]

I’ll try to replicate the conditions the next time I have a heavy pull, and run your testing procedures. It sure seemed like the alternator stopped charging for a few minutes, but again, I don’t understand the system well enough to say one way or another. 

[Tractorman]

It is quite possible that what you are saying is true.  You just won't know until you have a voltmeter attached to one of the batteries when the situation occurs.  If the PCM does turn off the alternator under those conditions, it could be normal - the PCM could be protecting the alternator by stopping unusual current flow under an abnormally low voltage condition.  Only a guess.

 

- John

 

 

[Mopar1973Man]

The green wire varies the ground to vary the charge rate. Since the vehicles has current draws the alternator will always charge some all the time match current loads.

[LorenS]

The thing that jumps out at me is that you were possibly drawing over 300 Amps for 30 seconds with the winch, then hoping that the 120 Amps for 60 seconds was sufficient to recharge the battery. But your fuel pumps, ECM, etc. were also drawing power. You drained the bucket with a firehose and refilled with the garden hose at only twice the duration.

Edited January 12, 2023 by LorenS

[Andyba20]

4 minutes ago, LorenS said:

then hoping that the 120 Amps for 60 seconds was sufficient to recharge the battery

Good point, I was doing the 30/30 more for the winch motor, and then waiting for the charging voltage to return to the normal 14.2 I see on mine, but yea I’m not really sure what the amp hours are on my 810 Everstart batteries. Or if that even is a factor in this scenario. 

[IBMobile]

Along with the alternator being controlled by the PCM have you installed fuse in the blue wire from the PCM to the alternator to protect the PCM circuit board/ voltage regulator?

 

Alternator and PCM protection - Electrical - Mopar1973Man.Com LLC

https://mopar1973man.com/cummins/articles.html/24-valve-2nd-generation_50/51_engine/electrical/alternator-and-pcm-protection-r617/

 

 

[Andyba20]

4 minutes ago, IBMobile said:

you installed fuse in the blue wire

Busted. Not yet, it’s been on my list and it keeps getting pushed back with other repairs. 

[Tractorman]

Yup, you've been busted.  Shame on you!

 

Uh....?  I guess I should install mine, too.

 

- John

[Andyba20]

1 minute ago, Tractorman said:

Yup, you've been busted.  Shame on you!

Haha! I have to weigh the benefits of a mod vs my ability to find new ways to screw things up. My rule with electronic mods is to wait for a nice sunny day when I can take my time and dedicate my complete undivided attention

[IBMobile]

1 hour ago, Andyba20 said:

wait for a nice sunny day when I can take my time and dedicate my complete undivided attention

You're going to install a fuse in a wire; not taking it out on a date.

[Andyba20]

Alright I’ll get it finished tomorrow. Then on to the Tappet cover. 

[W-T]

@Andyba20

23 hours ago, Andyba20 said:

Ambient temps around 45*. So was the pcm giving a command not the alternator not to charge for a minute,

 

The ambient temperature is measured by the IAT to allow the ECM to adjust perimeters for proper engine running conditions. 

 

The battery temperature sensor on the drivers side is the element that determines charge rate. The thermal change or stress to the battery case is provided to the PCM via this particular sensor to limit the amount of current generated by the alternator.

 

The "two" batteries being less than 4 months old...disconnect the adjoining cables and with your DVM verify both batteries are equal in static DC potential. Each battery should reflect nearly identical voltage levels. One may show 12.6 volts the other may show 12.5 volts and this is acceptable.

 

If you have one storage cell at 12.2 (just approximate) and the other is 11.5 volts (as an example) this indicates a damaged cell within the battery that is showing 11.5 volts.

This damaged cell will continually draw current from the healthy battery and this discharge will pull the 'head charge" off the healthy storage cell in this parallel configuration.

 

NOTE: All storage cells are static at 12.6 volts. Anything less than 12.6 is considered discharged and requires replenishment via the charging system.

 

Ground is so very important especially in "high current" generation systems. Please examine your alternator's mechanical mounting system. The case of the alternator is the main ground reference for your diode stack within the alternator. The PCM controls the charge as Mike @Mopar1973Man has pointed out utilizing the "green wire" from the PCM as a variable "ground reference" to vary the amount of current being generated. If the integrity of the ground between the alternator's case structure is compromised the PCM can not track charge rate correctly.

 

Under high current demand (operating a wench) for extended periods of time all connections of the parallel configuration must remain cool to touch. Any notable thermal variation between separated terminals when conducting high current demand is an indication of poor continuity at the terminal where you note the higher temperature.

 

23 hours ago, Tractorman said:

Think of it this way - every battery cable has four connections.  Example (using the battery crossover cable):  passenger side battery to clamp, clamp to passenger side cable wire,  cable wire to driver side clamp, and finally clamp to driver side battery. So, one wire - four connections.  Multiply that by number of cables used means a heck of a lot of connections.  Something that I always remind myself - an electrical system can only perform at the level of its worst connection.   It only takes one poor connection to dramatically reduce performance - especially under heavy electrical load.

 

I recommend hooking up your winch to a heavy continuous load.  With a helper operating the winch, use your voltmeter to check voltage at each battery and relevant connection points while under load.

Tractorman's  contribution here needs to be considered Biblical, especially when sinking current loads of 100 amps or more!

 

The batteries individually, have a CCA (cold cranking amps) most likely exceeding 750 Amps each and in parallel this accumulates to 1,500 Amps. This is substantial and total energy available (Ohm's Law) 12.6 volts X 1,500 Amps = 18,900 Watts of energy. The highest current demand these CTD's see on a regular basis is the starter motor when activated to start the engine. Current demand can approach 700+ Amps but, this demand, under normal conditions, occurs for a short period of time and the system is well designed to perform this duty.

 

The wench device is another high current demand device. The operation exceeds the intermittent time of the starter motor at half the current demand but, 280 to 300 Amps is a large demand to supply for a period of 5 minuets. The robust condition of your system is put to the test in this scenario and should be closely inspected.

 

This "wench" device needs to be checked in a simple static spin TEST to verify the integrity of the field windings.

1) Divorce the DC motor from the drive mechanism

2) Hand spin the armature to verify "free spin" without binding, it should feel uniform through a full 360' degrees of rotation.

3) Take a test-lead with alligator clips on each end and attach the alligator clips to the DC terminals on the motor, you are shorting the brush contacts on the armature that connect to the field windings of the DC motor.

4) Holding the motor steady, begin hand-turning the shaft, you will feel substantial resistance as you attempt to turn the armature a full 360 degrees of rotation. You are feeling the electromagnetic self-generation within the armature structure and it will resist your turning the shaft through the "entire" 360 degrees of rotation. 

 

You must NOT feel a loose spot! It resists you turning the full 360 degrees with very uniform physical resistance! If, as you turn the shaft (DC terminals are shorted together with the test lead) and you feel a "loose spot" where it "slips" easily as you turn at a very particular location on the armature's brush location, this indicates a shorted field within the windings. This is a bad motor winding of the wench's motor.

 

All DC motors can be examined for proper integrity in this poor-mans test procedure. It is a fast and accurate method to determine if an armature is shorted to it's adjoining contact, or, a field winding has shorted and is drawing excessive (massive) current as the armature spins the 360 degrees of rotation.

 

Rich Man's procedure.

 

1) Procure a 1.5 volt battery (AAA or AA or C cell) or D cell, do not use a full size 12 Volt auto battery. This test requires a very low voltage and current supply.

2) Two alligator test leads are required.

3) Carefully hook the test leads up to the battery + to plus and - to minus

4) Attach the ground first to the motor, then "as you hold the battery in your hand" connect the + lead to the motor. The low voltage (1.5 volts) will spin the motor "very slowly" in operation, be sure to allow the motor to spin a full 360 degrees.  PAY ATTENTION ! If, as you low-voltage, rotate the motor and it comes to a STOP, the battery in your hand will get very hot QUICKLY! This is the "bad spot" on the armature, QUICKLY remove the battery voltage from the motor. The battery will get hot so fast, along with the test-leads, a technician will know immediately to terminate the test...he has found the dead-spot within the motor.

 

A) low voltage test just "tickles" the field windings and the motor spins slowly to it's point of ERROR.

B) the low current supply of the battery will not cause additional damage or fire in the controlled test-procedure.

C) key aspect, low voltage reveals the error quickly.

 

Review, a "load" or DC motor spinning at a standard rate of speed, being supplied a huge amount of current (parallel DC storage cells) will "spin passed" the dead spot but, every rotation encounters the dead spot and at that very moment it sinks excessive current that is dissipated in the form of heat and NOT kinetic energy of motion. This is an extreme loss of efficiency and will pull the head charge off storage cells quickly.

 

Your procedure of operating a wench is correct, timed operation and rest periods between "grunt" effort and the CTD at idle should allow this to function correctly. The timing sequence of operation you posted, along with the "quick" low voltage warnings cause me to encourage your examination of each connection (thermal change) the alternators ground integrity (the physical mounting) and the condition of your wench motor's armature/field windings.  

 

Be sure the drivers side battery temperature sensor is firmly in the baby's butt.

 

W-T

 

 

 

 

 

[Mopar1973Man]

9 minutes ago, W-T said:

The ambient temperature is measured by the IAT to allow the ECM to adjust perimeters for proper engine running conditions. 

 

Just a bit of info on this... Typically on average the IAT will show approximately +40*F over outside air temperature. This is not a good measurement of ambient air temperature. Then the only thing the IAT does is control the grid heater for length of time it will run to heat for start up. As for after starting if the IAT falls below +80*F then the timing will shift to add about 3 to 4 degree advanced. Above 80*F then it uses the normal timing. Optimal IAT is 100*F to 140*F.

 

11 minutes ago, W-T said:

The battery temperature sensor on the drivers side is the element that determines charge rate. The thermal change or stress to the battery case is provided to the PCM via this particular sensor to limit the amount of current generated by the alternator.

 

Battery temperature sensor is for the primary use of charging the battery. It measures the case temperature to prevent boiling the battery with excessive charge voltage. Most don't know that the battery temperature sensor also controls the grid heaters post heating cycle. Just tidbits to add.

 

Good post @W-T...