MS3X input questions
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MS3X input questions
Hello again, I have some questions about inputs wiring and calibration.
I bought 2 pressure sensors(for oil and fuel)
http://www.ebay.com/itm/Oil-Pressure-El ... 2a1bd49f04
An oil temperature sensor
http://www.ebay.com/itm/Oil-Water-Temp- ... 0e&vxp=mtr
An EGT sensor
http://www.ebay.com/itm/EGT-EXHAUST-TEM ... 2a10add742
And the new knock module to replace my KnocksenseMS.
I will also connect my VSS.
-First of all I want to ask something about my OEM CLT. From a little research on the net my M42 engine uses the same sensor as the E30 325 which TS already has. I have an 93C thermostat, but I see normal operating temperature 100C. Is this normal? Shouldn’t I see an operating temperature near 93C?
-Pressure sensor:
I’m going to use a bias resistor 72 Ohm (which is the average value) and found the voltage from the equation Vout=(Rsensor/Rbias+ Rsensor)*Vin.
-Oil temp:
When I bought the sensor I didn’t see that I don’t have its resistance on 0C and 150C to calibrate it. How can I?
-Knock module-EGT pins:
I have the V3 mainboard, so I don’t have the DB15. I need 2 unused hardness pins from the mainboard to wire my 2 knock sensors. I also need 2 pins for the EGT. As I see from the wiring diagram pins 3-13 are empty, can I use any of them?
-My OEM VSS sensor is a magnetic sensor that works at 4,7V. How can I connect it to MS? It has only Ground and 12V switch inputs.
Many thanks!
I bought 2 pressure sensors(for oil and fuel)
http://www.ebay.com/itm/Oil-Pressure-El ... 2a1bd49f04
An oil temperature sensor
http://www.ebay.com/itm/Oil-Water-Temp- ... 0e&vxp=mtr
An EGT sensor
http://www.ebay.com/itm/EGT-EXHAUST-TEM ... 2a10add742
And the new knock module to replace my KnocksenseMS.
I will also connect my VSS.
-First of all I want to ask something about my OEM CLT. From a little research on the net my M42 engine uses the same sensor as the E30 325 which TS already has. I have an 93C thermostat, but I see normal operating temperature 100C. Is this normal? Shouldn’t I see an operating temperature near 93C?
-Pressure sensor:
I’m going to use a bias resistor 72 Ohm (which is the average value) and found the voltage from the equation Vout=(Rsensor/Rbias+ Rsensor)*Vin.
-Oil temp:
When I bought the sensor I didn’t see that I don’t have its resistance on 0C and 150C to calibrate it. How can I?
-Knock module-EGT pins:
I have the V3 mainboard, so I don’t have the DB15. I need 2 unused hardness pins from the mainboard to wire my 2 knock sensors. I also need 2 pins for the EGT. As I see from the wiring diagram pins 3-13 are empty, can I use any of them?
-My OEM VSS sensor is a magnetic sensor that works at 4,7V. How can I connect it to MS? It has only Ground and 12V switch inputs.
Many thanks!
-
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Re: MS3X input questions
I wouldn't worry too much. Sensor and thermostat calibration are not perfect, and if your CLT sensor is not directly behind the thermostat, it's entirely possible that the CLT location really is at 100C and the thermostat is at 93C. Coolant temperature is not uniform throughout the engine.LoukakIS wrote: -First of all I want to ask something about my OEM CLT. From a little research on the net my M42 engine uses the same sensor as the E30 325 which TS already has. I have an 93C thermostat, but I see normal operating temperature 100C. Is this normal? Shouldn’t I see an operating temperature near 93C?
Makes sense.-Pressure sensor:
I’m going to use a bias resistor 72 Ohm (which is the average value) and found the voltage from the equation Vout=(Rsensor/Rbias+ Rsensor)*Vin.
Try calibrating it with ice water and boiling water, like this:-Oil temp:
When I bought the sensor I didn’t see that I don’t have its resistance on 0C and 150C to calibrate it. How can I?
http://www.diyautotune.com/tech_article ... lation.htm
Pins 3 through 6 are empty; 7 through 13 are grounds. I wouldn't try hooking an EGT probe up to a D-sub anyway; I'd probably cut a hole in the box to bring its wire in somehow.-Knock module-EGT pins:
I have the V3 mainboard, so I don’t have the DB15. I need 2 unused hardness pins from the mainboard to wire my 2 knock sensors. I also need 2 pins for the EGT. As I see from the wiring diagram pins 3-13 are empty, can I use any of them?
If it's a square wave, it should work with a ground triggered input.-My OEM VSS sensor is a magnetic sensor that works at 4,7V. How can I connect it to MS? It has only Ground and 12V switch inputs.
Many thanks!
Matt Cramer -1966 Dodge Dart slant six running on MS3X
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Re: MS3X input questions
I don't know if you're aware of it but you'll need an amplifier circuit for the EGT probe. You can't connect it directly to an ADC input.
Jean
Jean
Re: MS3X input questions
Once again many thanks Matt!
Yes racingmini, I'm waiting AD595CQ to arrive...
I'm a little bit confused about the EGT. You mean that I have to solder the cromel-alumel cables directly on the AD595CQ?
Yes racingmini, I'm waiting AD595CQ to arrive...
I'm a little bit confused about the EGT. You mean that I have to solder the cromel-alumel cables directly on the AD595CQ?
Re: MS3X input questions
Hello again, I have one question.
If I wan to use js4 & js5 on MS3X should I follow the instructions for MS2, or can i give them correctly 0-5V?
thank you
If I wan to use js4 & js5 on MS3X should I follow the instructions for MS2, or can i give them correctly 0-5V?
thank you
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Re: MS3X input questions
Yes you can use ADC6,7 just like on an MS2 and yes they are 0-5V inputs just the same.
James
James
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Re: MS3X input questions
thank you James, if I understand correctly I don't have to do any changes to the ini file.
I just have to make the circuit.
Right?
I just have to make the circuit.
Right?
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Re: MS3X input questions
No ini file editing is required.
Select the appropriate input on the EGT page.
James
Select the appropriate input on the EGT page.
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk
My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
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Re: MS3X input questions
Perfect!
OK for the EGT, but I also need to use the other ADC for my bypass valve possition sensor. Should I use the chematic on MS2 analoc iput docs?
OK for the EGT, but I also need to use the other ADC for my bypass valve possition sensor. Should I use the chematic on MS2 analoc iput docs?
Re: MS3X input questions
My exhaust manifold is a 4-1 type.
So I'm wondering if it is best to fit the EGT 1-2" after the 4th cylicer exhaust valve(which is the hotest I assume) or in the place where the 4 runners met.
Any ideas?
So I'm wondering if it is best to fit the EGT 1-2" after the 4th cylicer exhaust valve(which is the hotest I assume) or in the place where the 4 runners met.
Any ideas?
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Re: MS3X input questions
The EGT probe leads dont have to soldered DIRECTLY to the AD595 but they should be soldered to copper pads on a PCB (or plated perfboard) that is physically close to the AD595 input pins. It is possible to use connectors and extensions but they must be thesame type wire as used by the probe. There is an explanation of why and a suggestion for a PCB layout on page 4 of the AD595 datasheet http://www.analog.com/static/imported-f ... 94_595.pdf.LoukakIS wrote:Once again many thanks Matt!
Yes racingmini, I'm waiting AD595CQ to arrive...
I'm a little bit confused about the EGT. You mean that I have to solder the cromel-alumel cables directly on the AD595CQ?
A2 VW GTI 9A - MS3/3X
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Re: MS3X input questions
In theory this is correct but if you use connectors that are close enough to the AD59x to be at the same temperature, the temperature correction done in the chip will do a good job of compensating for it. So unless you are making a lab precision unit, the use of generic connectors should not be an issue.walterclark1 wrote:The EGT probe leads dont have to soldered DIRECTLY to the AD595 but they should be soldered to copper pads on a PCB (or plated perfboard) that is physically close to the AD595 input pins. It is possible to use connectors and extensions but they must be thesame type wire as used by the probe. There is an explanation of why and a suggestion for a PCB layout on page 4 of the AD595 datasheet http://www.analog.com/static/imported-f ... 94_595.pdf.LoukakIS wrote:Once again many thanks Matt!
Yes racingmini, I'm waiting AD595CQ to arrive...
I'm a little bit confused about the EGT. You mean that I have to solder the cromel-alumel cables directly on the AD595CQ?
However, if you need to make an extension to connect the probe(s) to the EGT circuit then you will need to use the proper thermocouple connectors and wires.
Jean
Re: MS3X input questions
Ok I got it, thank you guys. Will it be better if I sorten the EGT cable as I can?
My EGT is this one (http://www.ebay.com/itm/EGT-EXHAUST-GAS ... 2a23f49073). Its operating range is 200C to 1200C will that be a calibration issue?
My EGT is this one (http://www.ebay.com/itm/EGT-EXHAUST-GAS ... 2a23f49073). Its operating range is 200C to 1200C will that be a calibration issue?
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Re: MS3X input questions
No. The wires in the cable are the correct K-type thermocouple wires so they won't affect the temperature reading. However, depending on the probe you may need to ground the shield to keep noise down. And route the cable away from the usual noisy components.LoukakIS wrote:Will it be better if I sorten the EGT cable as I can?
As for the calibration, this is only dependent on your AD595 circuit. The K-type thermocouple response is the same for all probes.
Jean
Re: MS3X input questions
I want to use IAC1A for A/C idleup output,IAC2A for a programmable output and IAC1B-IAC2B to drive the two DIY analog inputs through the harness to JS4-JS5.
I’m going to connect:
-IAC1A to JS0
-IAC2A to JS2
-1st analog input signal to pin 27 and IAC1B to JS4
-2nd analog input signal to pin 31 and IAC2B to JS5
Is this correct
I’m going to connect:
-IAC1A to JS0
-IAC2A to JS2
-1st analog input signal to pin 27 and IAC1B to JS4
-2nd analog input signal to pin 31 and IAC2B to JS5
Is this correct
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Re: MS3X input questions
Why are you wiring the B sides to the analog inputs?LoukakIS wrote:I want to use IAC1A for A/C idleup output,IAC2A for a programmable output and IAC1B-IAC2B to drive the two DIY analog inputs through the harness to JS4-JS5.
I’m going to connect:
-IAC1A to JS0
-IAC2A to JS2
-1st analog input signal to pin 27 and IAC1B to JS4
-2nd analog input signal to pin 31 and IAC2B to JS5
Is this correct
Also note that these put out 12 volts - the analog inputs are designed for 5 volts max.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Re: MS3X input questions
Because I thought that pins 27 and 31 are empty on the connector side so I wanted to use these pins to drive the analog sensor inputs inside the box.
What is giving 12V? I made it like this, is it ok?
Konstantinos
What is giving 12V? I made it like this, is it ok?
Konstantinos
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Re: MS3X input questions
Sorry, misread what you were doing.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Re: MS3X input questions
My A/C control unit is giving 12V output when I press the A/C button, so I'm considering to use pin 29 on MS3X(nitrous in) as idleup Input. The manual said "JP8 is jumper for a pullup on the "Nitrous in" input. Normally the nitrous system expects a 12V input here and the jumper should be omitted. " If I want to use the 12V nitrous input should I solder a resistanse instead of the jumper, or should I just connect my A/C control unit output to pin 29 without anything?
Konstantinos
Konstantinos
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Re: MS3X input questions
That jumper shouldn't be fitted. I can't think of any option in the code where it makes sense to install it. Just remove it.
James
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk
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MSEXTRA documentation at: http://www.msextra.com/doc/index.html
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