aisystems15 Posted July 5, 2014 Report Share Posted July 5, 2014 I want to use the volt in as a temporary temp measurement for a coolant/oil cooler . My question is which will be the best to pick and how would I calibrate that. I'm using the VDO 180/9/1 temp sensor. I think I would use the GP temp with external pull-up . How would I calibrate that? Quote Link to comment Share on other sites More sharing options...
Dave Kriedeman Posted July 5, 2014 Report Share Posted July 5, 2014 Hi , you can use any VOLT INPUT as a TEMP input as long as you use an external pull up resistor. You can find how to terminate this setup in the HELP file, under analogue inputs. You will then need to setup a CAL TABLE to suite your temperature. You will need to know the volt/ degrees c or ohm/ degrees c scaling of your temp sensor to create a proper CAL TABLE. Setup your volt input as GP TEMP and select a CAL TABLE. I have attached a couple of different examples for you of how you can achieve this. Regards Dave. Quote Link to comment Share on other sites More sharing options...
aisystems15 Posted July 6, 2014 Author Report Share Posted July 6, 2014 Hey Dave, I must be doing something wrong. I set it up as follows; volt 7 as gp temp input 5 volt source as pull up to the signal line cal table from the VDO web site My indicated out put is 0 C* when the comparable parameter is 22C* I guess I could have the cal table wrong, but do you think everything else is ok? Thx JH Quote Link to comment Share on other sites More sharing options...
Dave Kriedeman Posted July 6, 2014 Report Share Posted July 6, 2014 Hi, I forgot top ask earlier ,sorry. Is the sensor a NTC or PTC (negative temp co efficient or positive temp co-efficient). what value resistor have you used for your pull up from 5 volt to the analogue volt input ? (1K = 1000 ohms). what CAL TABLE did you use and how have you set it up ? If you are unsure of your CAL TABLE setup, post up the volt or ohm to degrees C or F calculation relationship and I will generate a CAL for you. Can you please post the P/No of the sensor , I did a search on the VDO site and it doesn't exist under that number. Regards Dave. Quote Link to comment Share on other sites More sharing options...
aisystems15 Posted July 6, 2014 Author Report Share Posted July 6, 2014 Let me check on a few of the questions. I don't have a resistor at this time. I'll install a 1k next time I'm there. I'm wanting to use 4 volt in 7,8,9,10... still !K ? Do they need separate resistors or can I daisy chain the 5v? The VDO part # is 801/9/1 . Sorry. Typo I filled out cal table 2 using the VDO characteristic table ohms to c* table 16. I'll check with VDO tomorrow if that's the correct one for my sensor. Thx JH Quote Link to comment Share on other sites More sharing options...
Dave Kriedeman Posted July 6, 2014 Report Share Posted July 6, 2014 Hi, you must run the 1K ohm (1000 ohm resistor) for this to work. So you are planning on running 4 ANALOGUE VOLT INPUTS as TEMP inputs is this correct. All AN VLT I/P's must have a 1 K ohm pull up fitted to each input for them to work. DO NOT DAISEY CHAIN from one AN VLT I/P to the next otherwise the supply voltage will be less at each input. I have attached the schematics from the HELP file on how to setup the analogue volt input for TEMP sensors. Regards Dave. Quote Link to comment Share on other sites More sharing options...
aisystems15 Posted July 6, 2014 Author Report Share Posted July 6, 2014 OK. one 1K resistor per channel from 5V I'm using. I'll make that repair and check on my sensor with VDO and check back with results. thx. JH Quote Link to comment Share on other sites More sharing options...
Dave Kriedeman Posted July 6, 2014 Report Share Posted July 6, 2014 Hi, I would also suggest when you have everything connected and running with your laptop connected to your ECU and online, going to the RUNTIME VALUES by pressing F12 on your keyboard, then go to the ECU STATUS TAB. On the left hand side of this window will have ECU VOLTAGES, look at the Analogue Supply Volts and make sure you haven't overloaded the circuit. This voltage should be very close to 5 volts at all times. Regards Dave. Quote Link to comment Share on other sites More sharing options...
aisystems15 Posted July 8, 2014 Author Report Share Posted July 8, 2014 Hey Dave, OK, I've installed the individual 1k resistors. ecu status tab -ecu voltages box--analog supply (v) 5.01 -ecu status box--all green-5v analog suppy ok analog tab -analog data volt box--an v7,an v8,an v9,an v10 all gp temp (ext pull-up) (c*) indicate 75 -analog status box--all green,all ok Does all that sound OK? Interesting other info when I measure the 5 volt line at the map xducer i see 5 volt. When I measure the voltage at the new temp sensor I read 2.5 volt I'm still waiting to hear from VDO regarding my cal table to make sure I'm reading the right one. Thx JH Quote Link to comment Share on other sites More sharing options...
Dave Kriedeman Posted July 8, 2014 Report Share Posted July 8, 2014 Hi, your voltage will read lower because you have a 1 k ohm resistor in parallel with you an volt input, you must consider that the resistance of the sensor is added also, which in total will reduce the voltage, this voltage will go up and down dependant on the temperature which will vary the sensors resistance value. If your Runtime values show the 5 volt supply as being happy then all should be good. You just need to clarify your sensor calibration is correct for each of your new temp inputs and you should be good to go. Regards Dave. Quote Link to comment Share on other sites More sharing options...
aisystems15 Posted July 10, 2014 Author Report Share Posted July 10, 2014 Hey Dave, I got a response from vdo and they said that info is proprietary and would not verify the characteristic table even though I can see it on the internet. they say I can't use their product on anything except vdo gages. I'm not sure what to do now. Any suggestions?? Everything is green and looks ok except the indication says 75 when my comparable coolant temp says 22. It's got to be my cal table? JH Quote Link to comment Share on other sites More sharing options...
aisystems15 Posted July 10, 2014 Author Report Share Posted July 10, 2014 Hey Dave, Just to keep you in the loop...I got some better advice on the cal table( not from VDO!) and when I entered the new cal table the indicated temps on my test an volt in is the same as the existing coolant temp. And I am trying to measure the coolant temps as well as some oil temps, so I'm going to try it. Thx for all the help! JH Quote Link to comment Share on other sites More sharing options...
Dave Kriedeman Posted July 10, 2014 Report Share Posted July 10, 2014 Hi, Sorry for the delayed reply, I have been tuning two different cars with V88's for two different workshops on the same day, driving back and forth as they fixed problems. Today I am fully flogged. Anyway, that is very good news regarding your sensor cals, I haven't really come across a sensor that a cal can't be created for. Sometimes it calls for being a little creative ,using hot air guns, freezers, electronic thermometers, laser temp guns and a multimeter Good luck with your project and if you get stuck , just post away. Regards Dave. Quote Link to comment Share on other sites More sharing options...
aisystems15 Posted July 14, 2014 Author Report Share Posted July 14, 2014 Hey Dave, So, I ran with my test sensors in place. I need a higher temp. I'm using cal table 2-ohms=temp-but it tops out at 75C*. Someone told me I could add cal points or creat my own custom cal table but I didn't see anything in the help menu regarding this? Can I get the Vi-Pec cal table to indicate higher. Maybe 100C*? Let me know, JH Quote Link to comment Share on other sites More sharing options...
Dave Kriedeman Posted July 14, 2014 Report Share Posted July 14, 2014 Hi mate, there are two different types of CAL setups you can use , CAL type 1 to 3 and the CAL and CAL types 4 to 6. I have supplied a screen shot of both types setup to suit your application. Either one will work, but the first Cal file setup using CAL 1 will be more accurate due to exact ohm or volt scaling that have been supplied by the manufacturer. In the CAL table 1 example you adjust the starting temp value and the table increments to suit your needs. Regards Dave. Quote Link to comment Share on other sites More sharing options...
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