Block heater ?

[BK]

That's not quite accurate. The ECM depresses the needle on the voltage gauge during a postheat cycle, whether the heaters actually warm up or not. A depressed needle in and of itself is not an indication of functional heater grids.



Ryan

On my 99, the voltmeter goes exactly when the headlights dim.

I don't know what influence the ECM has on my Volt meter (a 99), but it's right there with the dashboard lights dimming and the head lights dimming.

And I can hear a change in the tone of the engine noise as well.



Is the voltmeter handled different in the different Gen's of trucks?

 

[steved]

On my 99, the voltmeter goes exactly when the headlights dim.

I don't know what influence the ECM has on my Volt meter (a 99), but it's right there with the dashboard lights dimming and the head lights dimming.

And I can hear a change in the tone of the engine noise as well.



Is the voltmeter handled different in the different Gen's of trucks?

Ryan probably assumed you were talking 3rd gen, not second generation... the ECM controls most (if not all) the guage readings on the 3rd gen trucks.

 

[steved]

SteveD,

I've noticed the same thing has you when it's damn windy out, cold, and I go in and wait for the heater wait light to go out.



as far as the 99 heater...

I assume your using the same outlet and extenstion cord when you measure the current draw as the 04?

Is the plug on the 99 in good shape?

I've gone thru one already on my 99, it got hotter then heck and either didn't make a good connection, or I only drew ~3. 5amp, or more wiggeling got it to near 5amps.

It was a fire on my bumper waiting to happen. Finally replaced it. And it prompted me to start using a wattmeter on mine all the time. got tired of running to the basement to check it, so rigged up some branch ckt monitoring to my PC.

We simply assumed it was different for the simple fact they are supposed to be two different wattages...

 

[BK]

We simply assumed it was different for the simple fact they are supposed to be two different wattages...

Ah, I didn't know they were suppose to be different between the Gens.

I assumed the other way, that they were the same.

 

[BK]

The rating has me wondering and so I started looking.

I can't find anything in my FSM.



I did find some numbers from an OEM replacement mentioned in another forum and starting tracking that p/n down.



Central Diesel Inc.

about a 1/4 of the way down is the listings for the Cummins powered Dodge applications.





Atleast from that manufacturer, it seems the element is different physically , one configurtion for 1989-2001 , and a different configuration for 2002-2007, but the rating is the same at 750watts.

A 1,000 watt unit is specified for the 8. 3 block.



I found the ratings here for those p/n's...



. : TAC :. Transportation Accessories Company



I haven't so far found Dodge p/n's online.

Anyone else know of the p/n's?





------------------

3500022 vs 3500030

After looking closer, and reading some more listings, it seems the difference between the two p/n's called out, is one is the recpetical in the block, and the other is meant to replace a freeze out plug in the block.

And the listing above for the earlier models, is for a freeze out plug replacement, which includes my year. But I know mine is dedicated recpetical in the block. So those listings don't make sense.



------------------



Found a few source selling Cummins branded boxed heaters.

One on Ebay, and some deisel parts shop online.



05003619AB (thinking is is the Dodge part that the store is listing-all his other parts of mopar boxes. )

"Fits years 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007"



Sources with it specifically marked a Cummins p/n 3928341

"Application: 98. 5 - 09 5. 9L CUMMINS ISB. QSB DIESEL HEATER"

Another source... .

"Dodge Ram 2500 - 3500 1998 - 2003"



Going to Fleetguard, the 3928341 comes up.

http://www.cumminsfiltration.com/pdfs/product_lit/americas_brochures/MB12-00-4.pdf



"3928341 750watts 120vac ¾ NPT Immersion ISB, QSB"



FYI from the fleetguard listing... .

"3306006 1000watts 120Vac ¾ NPT Immersion ISC, QSC Series (8. 3L 505 CID)"



I would assume the heaters in our blocks from Dodge, are actually factory Cummins / Fleetguard... ??



------------------------------------------------

 

[JimB1]

Hey BK, Nice detailed response.



Last I've done detailed reactive AC circuit analysis was when geeks still used slide rules.



Still got my very nice set of metal Picketts and use them from time to time.



I avoided using too much electrical technical terminology so that our posts remain user friendly to all.



Reading back thru your original post I see your first measure was 675 W and 2nd measure was 687 W calculated from DAC (digital to analog converter) data.



I'd originally mistakenly read the 675 W as data comming from a spec sheet.



Is the 12 W variation from two different measuring methods, ie,calibrated wattmeter then DAC's with calculation, taken at near the same circuit point, as in somewhere near house circuit breaker panel?



Assuming both methods measure true power and you ohmmeter at those same test points for 18-20 ohms (and 119. 7 V) then there was too much calculated discrepancy to call it resistive line lose, but made me wonder if a small amount of heater element inductive coupling might be suggesting apparant power, tho' sill small in amount, was the answer.



Using P= E squared/R gives (796-716) W for 18-20 ohm load.



Using your first wattmeter figure, 675 W, gives about (121-41) W discrepancy that I took a guess and attributed it to heater element inductive coupling.



How important is all this?



Beyond being interesting viewpoints to converse about, not much.



My slide rules need some lube, should I use synthetic or dino?

 

[BK]

JimB1,



Thanks. That's what I like about the forum, real info, to help. But I hope we aren't hijacknig the thread, but I think the info is usable, even though we are getting into some detail.



So with that...





"My slide rules need some lube, should I use synthetic or dino? " LOL, I think that's another thread!

I think I heard from a lube expert that actually in most cases the dino oils have a better shear strength than syn's !??! So maybe dino is a better choice?



When I was in school we were told to bring in a slide rule on the 1st day, were introduced to it, then told to throw it out, and bring in a TIxx (can't remember the number) by the end of the week.



For me it's been since the mid 90's since I've done design work for power converters. My ac design involved power quality, active PFC front ends and input and output filters for SMPS (for FCC and Mil 461 and tempest), and loop stability in the power convters we designed, mostly SMPS, some linears.



Let me go back and look.

Cause some of my numbers were from my wattmeter (memory), others were from the DAQ.



So lets quantify and clearify... .



"I measured mine and it came in at 675 watts with a watt meter".

From the wattmeter, on that day, with what ever the applied voltage was... it varies, which of course changes the resultant wattage. I've seen it go up, and down. But when I lived with the wattmeter instead of my remote monitoring, I just used to peer down the basement steps and look for something above 650 to make me happy that it was working and that the plug and extension cord recpetical was happy and not ready to burn down my bumper.

I've seen 685w commonly as well in the past. I just took a medium number from memory of the use of the wattmeter.



When I used the wattmeter, it was plugged into the very same X10 appliance module (relay - not soft switching), same outlet, and used the same extenstion cord.

The " transducers ", or sensor xfmers for voltage and current have shunt resistors that need to be calibrated. I calibrated it to the wattmeter to with in a few % at 120Vac applied (used a variac).



"there is 119. 7Vac rms applied, and it's drawing 5. 74A. " (687. 078w / 20. 85ohms)

was from that very moment I wrote the post this morning, from the display on the software, on my PC from the DAQ.



Before I stepped out to lunch I think I saw 127. x at ~2pm, don't remember the current. I can go back into the logs and look and see if memory serves me correctly.

(I work out of my home office, no one around here during the day = higher Branch ckt voltages, drives some of my cheaper UPSs crazy mid day and not surprised for it to be high mid day. )



Lets fire up the software and turn it on while writing this...

I see 121. 3 @ 5. 80 = 703. 54 watts / 20. 9 ohms

earlier. . "119. 7Vac rms applied, and it's drawing 5. 74A" = 687. 078w / 20. 85ohms.



Took a screen snapshot... .

Voltage went down a bit when I went back for the screen grab.

comes out to 697w / 20. 86ohms

#ad

 

[BK]

Oh, and to bring the rating into bear from the FleetGuard flyer for the quantifying... ...



750Watts @ 120Vac = 6. 25 amps / 19. 2 ohms.



So it splits the difference of the 18 ohms mentioned earlier, and my 20. 85 ohms (total ckt). .

We also need to factor in , and a likey variable, calibration of the DMM the 18ohms was measure with. Being off by 1 ohm doesn't concern me, back to being with in measurement errors.

The 18oms wasn't shared with LSDs... could have been 18. 5 ohms.

As well, consider other tolerances... winding tolerance?

His heater winding could be lower in resistance than a normalized published number.



So with a published number of 750watts, giving us 19. 2 ohms (at 120Vac), I think there can be in the neighborhood of 1. 65 - 2 ohms total within all the physical contacts and wire lenthts in my ckt (and my heater could be on the higher side of it's tolerance).

There's a pretty big list of them...

Cord set plug (contact resistance) into the heater element on the block.

Plug on the cordset.

Plug on the extenstion cord.

Shunt resistance on transducer.

Plug in into x10 module.

Contact resistance of the relay on the X10 module.

Plug of the X10 module into the outlet.

25ft of extension cord.

All wiring of the transducers and to the X10.

 

[JimB1]

BK, Ok the sum of those quantifiers can account for variations we've discussed.



I recall TI-10 was the first popular Texas Instrument calculator, 4 basic arithmatic functions plus squares and square roots, maybe one memory register.



I went from slide rule to calculator then back to slide rule because I agreed with our best instructor who claimed that when you're still in the electronics learning curve and using calculators, you can't tell if calculated results are off by a box-car load until somewhere along the line you recognize that bad data isn't working.



With a slide rule you retain a intuitive feel for the analysis sequence and when some intermediate result is way off, it's much more obvious.



Going back to slide rule brought on a goodly amount of scoffing from others until I challenged all comers to speed calculations, the longer and more complex the number sets the better and easily beat them hands down most every time.



Fun times!

 

[BK]

I just noticed, I kept writing DAQ instead of DAC, duhh... don't know why. but did. . I see you knew what I meant.

data acquisition card or digital to analog converter (DAC). The modules I use can be programmed for 0-100mv, or 0-1000mv, or all different thermal couple types, including IR types. The modules talk via modbus rs485 rtu. I have a modbus rs485 to modbus ethernet bridge. I wrote the app in an HMI engine I had access to.



"I went from slide rule to calculator then back to slide rule because I agreed with our best instructor who claimed that when you're still in the electronics learning curve and using calculators, you can't tell if calculated results are off by a box-car load until somewhere along the line you recognize that bad data isn't working. "



That's are really good way of looking at it. Your the 1st I've heard describe it that way, and that makes sense.



Similar to what I've heard an accounted say, of you have a 1cent error, it really could be two very larger errros only a cent off of each other, so it must be found.



TI-10, that may have been it. . my 2nd had reverse polish notation.



I never lived with a slide rule.



For the past few good years, the kids have been required to have a graphing calculator for their advanced math course. . boy does that do a nice job of getting the kids to understand sine and co-sine and more. A long stride away from what we used.

It wasn't till I started my RF theroy did lots of the math I was taking kick in (undertanding that is).

It took practical applications for me to understand rather than memorize it.



Fellow forum members, sorry for the side bar.

 

[BK]

While we are at it and have been talking about the electrical characteristics of the block heater in our truck... .



There's one misnomer that pops up once in a while on the forum, I would like to revisit for this thread just so it's here, in case someone was thinking about it and wondering...



Our block heaters, being resistive, don't act like motorized power tools.

If you lengthen the extension cord between the outlet and the truck's block heater, the actual current draw will go down.



(Of course, size the extension cord correctly, don't think you can use a smaller gauge (thinner wire) type just because you are making it longer. Our heaters can draw 6. 25 amps (750watt size) or so. So size your extension cord for that current at a minimum. This is to protect the extension cord and your property not the heater. )(An added benefit is the lower the voltage drop in the extension cord, the more effective the block heater is).



(The current in the block heater doesn't increase like on a circular saw. The current on the motorized tools goes up when you lengthen the extension cord since they have a motor and depend on the right voltage, and the correct inductance at that voltage and rpm. Too long, to small of a gauge, (too much voltage drop = lower speed = higher current draw) and the tool can burn out when loaded due to excessive current in the windings of the motor (as well as the extension cord burn up from the excessive current). )

 

[rbattelle]

Wind does have an effect...

Of course, but that's not the same as being susceptible to "wind chill". Wind will carry away heat, but cannot cool the surface below ambient temperature.



"Wind chill" only applies to living things, and it's an attempt to account for the fact that it "feels" colder when it's windy.



And my comment about the voltmeter being depressed by the ECM applies only to 3rd gen trucks.



Ryan