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When Does Data Become Information, VMSpc

August 24, 2017, 09:59:12 pm

There is an excellent thread on this topic and I urge you go there to see what Roger and Dan had to say.

Paradox Development VMSpc

My reason for a new entry is that the Forum suggested automatically that I repost given the age of the prior thread.  The matter is data.....I am collecting data that I never had before.  Dan gives great ideas of setting for the ISM engine, 450 hp.  Others may have alternative parameters, please share.  Roger provided a direction of how to set the yellow and red warning signals.  So I can adjust some and I need to refine those.  But to recent data I got....an what is the information?

The question:  On this latest trip, I saw Oil Temp go as high as 208 degrees, more often staying around 199 - 203 degrees.  Ambient temp about 95 degrees.  At cooler times it stayed around 195-200.  But in the parameters some noted, the 208 sounds high enough to ask......is that level indicative of a problem?

Second question:  The manifold temp usually was quite a bit lower, but at one time it got to 116 degrees.  Given that was higher than the more usual 90 or so degrees, I am trying to understand why and does it indicate a problem, such as CAC failure?  Ambient about 95 degrees as I recall when this was seen.

Third Question:  I lost the odometer reading, it just set itself at 604,605 miles!  I turned off the vmspc and back on, it acquired the odometer reading in line with reality.......I cannot say it returned to the proper including the added travel or simply reset to the number where it went off sans that travel.  Why would it have set itself at 604,705 miles!?  Also, it would post miles in bits, not smoothly.  It might read 156,158.2 and then register again at 156,159.6 though at other times it recorded changed frequently by tenths.  Odd.

Observation:  Idle 725 rpm, Oil PSI 23.8.  At 65 mph, 1400 rpm, Oil PSI 34.5.

Retarder Temp no load, about 180 degrees.  Climbs to 250 degrees with heavy work, number I did not know before the VMSpc.  So I am sure I exceeded the 250 at some times in the past, lacking data.  Yet I am told by someone who spoke to Allision folks it would not have been a problem.  I cannot verify that.

Coolant Temp.  Often at 178 degrees.  Seldom goes above that,  at 108 degrees ambient and load I saw 210 degrees last year.  Worked to lower that by gear change.

Trans Temp.  Never saw it going yellow light or being much change.  Wish had kept a note on numbers for this report.

As Roger said and I saw, my start batteries were charging about 14.8 when started driving (yellow light).  After a few miles it settled into 14.4 volts (green light).

Data Lag.  I noticed a bit of a lag in showing the gear.  I could feel the downshift to 5th several seconds before the VMSpc posted it.  No problem it doing that.  I saw that on some other readout, forget which, but not tach.  Really appreciate the gear readout, did not have before.

I hope this helps someone.....seems a bit like gibberish as I read it!

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Re: When Does Data Become Information, VMSpc

Reply #1 – August 24, 2017, 11:44:48 pm

My  comments are mixed in below.

The question:  On this latest trip, I saw Oil Temp go as high as 208 degrees, more often staying around 199 - 203 degrees.  Ambient temp about 95 degrees.  At cooler times it stayed around 195-200.  But in the parameters some noted, the 208 sounds high enough to ask......is that level indicative of a problem?

** no info on this one.  203 seems my usual.

Second question:  The manifold temp usually was quite a bit lower, but at one time it got to 116 degrees.  Given that was higher than the more usual 90 or so degrees, I am trying to understand why and does it indicate a problem, such as CAC failure?  Ambient about 95 degrees as I recall when this was seen.

** I only see high manifold temps shortly after a engine start.  This leads me to believe (and I think I once read) that there is a manifold heater upon start.

Third Question:  I lost the odometer reading, it just set itself at 604,605 miles!  I turned off the vmspc and back on, it acquired the odometer reading in line with reality.......I cannot say it returned to the proper including the added travel or simply reset to the number where it went off sans that travel.  Why would it have set itself at 604,705 miles!?  Also, it would post miles in bits, not smoothly.  It might read 156,158.2 and then register again at 156,159.6 though at other times it recorded changed frequently by tenths.  Odd.

** My VMSpc software drops out once in a great while. Restarting the software updates the odometer correctly (as if it never dropped out).

Observation:  Idle 725 rpm, Oil PSI 23.8.  At 65 mph, 1400 rpm, Oil PSI 34.5.

Retarder Temp no load, about 180 degrees.  Climbs to 250 degrees with heavy work, number I did not know before the VMSpc.  So I am sure I exceeded the 250 at some times in the past, lacking data.  Yet I am told by someone who spoke to Allision folks it would not have been a problem.  I cannot verify that.

** Are you running Transyd or another synthetic fluid? If so, 250 is no issue based on reading I have done.  It should cool down pretty quickly after the retarder is no longer in use.  Retarder begins load shedding around 300.

Coolant Temp.  Often at 178 degrees.  Seldom goes above that,  at 108 degrees ambient and load I saw 210 degrees last year.  Worked to lower that by gear change.

Trans Temp.  Never saw it going yellow light or being much change.  Wish had kept a note on numbers for this report.

As Roger said and I saw, my start batteries were charging about 14.8 when started driving (yellow light).  After a few miles it settled into 14.4 volts (green light).

** Check in the parameter file settings.  It may have a set artificial add on (offset) to the reading coming in.  Roger pointed this one out to me.  Next time I take a actual voltmeter reading at the chassis engine batteries, I plan to set the offset for volts on VMSpc to give me an identical reading.

Data Lag.  I noticed a bit of a lag in showing the gear.  I could feel the downshift to 5th several seconds before the VMSpc posted it.  No problem it doing that.  I saw that on some other readout, forget which, but not tach.  Really appreciate the gear readout, did not have before.

** Mine lags a bit on the VMSpc as well. I usually feel the shift a couple of seconds before the VMSpc registers the gear.

I hope this helps someone.....seems a bit like gibberish as I read it!


** I have the latest version of VMSpc software.  HP and TQ have no readings. (ISM 450 engine selection).  Load reading works fine.

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Re: When Does Data Become Information, VMSpc

Reply #2 – August 25, 2017, 12:29:09 am

Mike and Dan,

"On this latest trip, I saw Oil Temp go as high as 208 degrees, more often staying around 199 - 203 degrees.  Ambient temp about 95 degrees.  At cooler times it stayed around 195-200.  But in the parameters some noted, the 208 sounds high enough to ask......is that level indicative of a problem?"

My oil runs in the high 190's but under some load it will go a bit more than that.  My yellow light comes on at 200°, I changed it to to 205° After checking with Cummins.  Even that is nothing to get concerned about.  At 210° I would probably ease off on the throttle and downshift.  I have not seen 210°.  Warmer ambient temps will push this up just a bit but it is mostly related to how hard the engine is working.

"The manifold temp usually was quite a bit lower, but at one time it got to 116 degrees.  Given that was higher than the more usual 90 or so degrees, I am trying to understand why and does it indicate a problem, such as CAC failure?  Ambient about 95 degrees as I recall when this was seen."

Manifold temps are usually 10° above ambient.  More if the work load or outside temps are higher.  It was 101° degrees coming across souther Idaho today.  Manifold temps were 110° or so.  When we got to Camp Walmart I let the engine idle for about 5-10 minutes to let things cool off.

"I lost the odometer reading, it just set itself at 604,605 miles!  I turned off the vmspc and back on, it acquired the odometer reading in line with reality.......I cannot say it returned to the proper including the added travel or simply reset to the number where it went off sans that travel.  Why would it have set itself at 604,705 miles!?  Also, it would post miles in bits, not smoothly.  It might read 156,158.2 and then register again at 156,159.6 though at other times it recorded changed frequently by tenths.  Odd." 

Trip odometers and the tank minder  will do that sometimes.  They will miss a bit of data and then display something goofy.  Sometimes, usually just wait a bit and they will catch up again.  Even if this gets lost the engine computer is keeping track of it.  VMSpc is just looking dormdata on the bus and displaying it.  Try <Advanced> <Engine Corrections> (check box) check both.  This will send regular requests for ODO and Fuel.  Should clear that up. This is typical for many Cummins engines.

"Idle 725 rpm, Oil PSI 23.8.  At 65 mph, 1400 rpm, Oil PSI 34.5."

Both are OK.  Especially when warm oil pressure will drop,at idle and go back up when you are driving.

"Retarder Temp no load, about 180 degrees.  Climbs to 250 degrees with heavy work, number I did not know before the VMSpc.  So I am sure I exceeded the 250 at some times in the past, lacking data.  Yet I am told by someone who spoke to Allision folks it would not have been a problem.  I cannot verify that."

Pretty typical.  250 is a good place to start changing strategy.  Lower gear, higher RPM will enhance cooling and reduce retarder loads.  Lower gear, then retarder, then brakes.  A notch or two back on the stick will get less increase in retarder temps than using the service brakes with the retarder switch on.  I have been doing a bit of mountin driving in the last month, we crossed several passes and the continental divide six times.  Slow down, drop into 4th, add a notch or two of retarder.  Try and use the service brakes less and before you go into curves.  My retarder gets close to 250 sometimes on long curving downhill runs.  Transynd is better abke to handle higher temps.

"Coolant Temp.  Often at 178 degrees.  Seldom goes above that,  at 108 degrees ambient and load I saw 210 degrees last year.  Worked to lower that by gear change."

Pretty normal coolant temp.  It was over 100° today, coolant was running 190-192, normal is 178. 

Like Dan said, check for an offset in the Parameter setting for the Battery Voltage.  I found a 0.8 volts offset, change to zero.

Actual gear has lag in it.  It is just the way it is. 

HP and Torque are calculated values.  Silverleaf knows this is an issues, most likely with the engine data.

You can set VMSpc to do data logging.  You pick what values you want to save and how often.  This can be downloaded into a spread sheet for more analysis.

Hope this helps.

Roger

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Re: When Does Data Become Information, VMSpc

Reply #3 – August 25, 2017, 11:23:29 pm

My oil temps run at 204+

coming back from utah last week the oil temps held at 215 to 216. .. I didnt have the readouts before to compare. After I installed the software I only drove 1 time but didnt follow all the readings as I do now. I feel I might have a turbo problem with the oil temps that high.. Ideas?

Never seen the yellow warning before  on the first run with the software.. I was rear ended and the car kinda tweaked the turbo oil tube that is under the turbo... it leaked from a mashed up gasket but after replacement I see the yellow warning almost constant.
It kinda has me on edge.

Nothing else besides the oil pressure at idle that shows a yellow and the retarder temps are up and down with no use.

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Re: When Does Data Become Information, VMSpc

Reply #4 – August 26, 2017, 12:29:01 am

I am not sure there is an exact correct reading for all engines of the same model.  What is important is that you figure out what your engine does in your coach given the way you drive and the places you drive.

Oil temps of 199 in my coach are pretty normal. If  205° is pretty normal in your coach then what you are looking for is changes from what you normally see.  So +10° from normal might be something you want to notice.

Oil temp sensors might have a +/- 1% accuracy.  At 200° that could be +/- 2°, easily the difference between what I see and you see. 

It is like tire pressure sensors.  I have rarely seen one that reads the same as my actual gauge.  Who is to say the gauge is any closer to actual than the sensor.  I can calibrate the sensors to read the same as my gauge but the exact number is not what I need to know.  What I want to know is when the pressure is changing, slowly or quickly. That is what you need to know to take action.

The readings at which the indicators change to yellow from green and then to red is arbitrary.  Set them to your level of interest and comfort.  They are there to signal you when you need to pay attention to something (yellow) or do something (red).

We were driving in the mountains today. A down shift and a notch or two of retarder keeps speeds where I want them.  Retarder temps never get out of the yellow range.  But step on the service brakes and the retarder works much harder and it can quickly pop into the red (250° on mine). These are very good tools to help you improve driving habits and skills.

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Re: When Does Data Become Information, VMSpc

Reply #5 – August 29, 2017, 09:13:10 pm

If you have VMSpc then you can set up data logging under the advanced menu.  You can select any of the gauges that you want to log whether you are displaying them or not.  You can select the frequency that you want to record information.

Here is a sample from my log from today.  We crossed over a 5200 ft pass at 91° and drove down to sea level at 68°.  The intervals were set for five minutes, the times we were in rest areas and getting fuel were removed.

This can be very helpful if you are trying to keep a close eye on some specific piece of data, coolant temp maybe.  These files can be imported into any of the common spreadsheets for you to use.  You log gear, speed, coolant temp, transmission temp, retarder temp and speed and see how these interact. 

So not only does VMspc display data for you it can record it too.  In fact there is a way to save a trip file and then replay it later like a simulation to see what happened when you weren't looking. 

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