AEM KType Thermocouple Amplifier 4 Channel 302204 User Manual

							
ADVANCED ENGINE MANAGEMENT INC. 
2205 126th Street Unit A, Hawthorne, CA. 90250 
Phone: (310) 484-2322 Fax: (310) 484-0152  http://www.aempower.com 
Instruction Part Number: 10-2204 Rev 0 
©  2005 Advanced Engine Management, Inc. 
   
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Installation Instructions for:  30-2204   
4 Channel Thermocouple Amplifier 
 
WARNING:
 
 
 
 
 
 
This installation is not fo  the electrically or mechanically 
challenged! Use th th EXTREMEr
is sensor wi
,!
 caution! If you are 
t 
uncomfortable with anything about this, please refer the 
installation to an AEM trained tuning shop or call 800-423-0046 
for technical assistance. You  should also visit the AEM 
Performance Electronics Forum at http://www.aempower.com 
 
NOTE: AEM holds no responsibility for any engine damage tha esults from the misuse of this product!
 r
 
 
y and should 
never be used on public highways. This product is legal in California for racing vehicles onl 
						

							
   The Advanced Engine Management (AEM) 4 channel thermocouple amplifier revolutionizes 
temperature measurements by providing labora tory grade accuracy for your temperature 
measurements. The accuracy is guaranteed to be be tter than 1% full scale, even at the extremes 
of the temperature range. It is designed either  for integration into vehicles already fitted with 
aftermarket ECU’s or other devices that can accept an analog signal for either analysis or 
logging. Alternately, an RS-232 output is availabl e to allow other programmable devices to use 
or display the thermocouple temperature data. 
 
   AEM achieves it’s accuracy by  starting with a 100% surface mount PCB. The four differential 
temperature inputs are fed into an A/D converter then fitted using a 3 stage, 8th order polynomial 
curve fit. This value is then compensated  using our on board cold junction temperature 
measurement. The temperature values are output  on four seperate 0-5v analog outputs and a 232 
serial datastream.  
 
   The thermocouple amplifier can be moun ted in the engine compartment or under the 
dashboard. It is very light and can easily be  mounted with Velcro or via the mounting holes. 
 
CONNECTION 
   When routing the thermocouple wires to th e amplifier, make sure to only use K-type 
thermocouple wire and only use  K-type thermocouple connectors. DO NOT use any other type 
of connector or material in the wiring between  the thermocouples and the amplifier or massive 
errors will result! The required  connectors to plug into the thermocouple amplifier are the “mini 
blade type”. 
 
The 9 wires should be hooked up as follows: 
 
Color  Marking  Connection 
Red    BATT POS    Switched +12v In 
Green    TEMP 1     Temp #1 0-5v Output 
Pink    TEMP 2     Temp #2 0-5v Output 
Brown   TEMP 3     Temp #3 0-5v Output 
Orange   TEMP 4     Temp #4 0-5v Output 
Yellow   RS-232 TXD     RS232 Transmit 
Blue    RS-232 GND    RS232 Ground 
Grey    SIGNAL GND   Signal Gnd (used if  a differential input is required) 
Black  BATT NEG   Battery Ground 
 
THERMOCOUPLE 
   A thermocouple is a device that contains 2 differing types of metal joined at the end. The 
junction between two differing metals generates a  voltage which is a function of the temperature 
at the junction point. While most  any two metals can be used, specific materials have become the 
standards because of the characteristic  temperature sensitivities they possess. 
 
   The  K-Type  Thermocouple  (Chromel/Alumel)  is a general purpose thermocouple that is low 
cost and available in almost every type of co nfiguration. This is the most common type of 
thermocouple in use today.  
 
   While the output voltages of different ther mocouple types are known and tables are available 
to show the output voltages generated at any gi ven temperature, you can not simply monitor the 
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voltage given by a thermocouple with a multi-meter. This is because the thermocouple acts as a 
differential device between the junctions and the connection of a multi-meter creates a junction 
at that point as well. The voltage supplied is for the difference of the temperature at the two 
different ends of the thermocouple so the output voltage will be for the temperature difference 
between the two points, not the absolute temp erature at the measurement tip. This makes 
knowing the temperature at the connector critic al to getting an accurate measurement. The 
connection temperature is known as the cold ju nction temperature and a compensation must be 
included for it’s effect. This is very important as  the error in the measurement of cold junction 
temperature will be directly reflected as an error in the measured temperature from the 
thermocouple. The AEM Thermocouple Amplifier has an internal Cold  Junction Temperature 
sensor to ensure the  accuracy of the output. 
 
 EXAMPLE: If the tip of a thermocouple is at 7 50C and the connection device, or cold junction 
is at 100C then the output for the thermocouple  will reflect 650C. The cold junction temperature 
compensation must be added to the measured  value to get the proper answer, 750C. The AEM 
Thermocouple amplifier performs all necessary compensations for the cold junction temperature 
so you don’t have to worry about it. 
 
ANALOG OUTPUTS 
All four temperature channels have high accuracy, 0-5V analog outputs. The calibration is: 
 
Temperature (C) = Volts * 200 
Temperature (F) = (Volts * 360) + 32 
 
Example: If 1.45 volts were output: The temper ature in Degrees C would be 1.45 * 200 = 290C  
The temperature in Degrees F would be (1.45 * 360) + 32 = 554F 
 
Volts Deg C Deg F  Volts Deg C Deg F  Volts Deg C Deg F 
0.00 0 32  1.70 340 644  3.40 680 1256 
0.10 20 68  1.80 360 680  3.50 700 1292 
0.20 40 104  1.90 380 716  3.60 720 1328 
0.30 60 140  2.00 400 752  3.70 740 1364 
0.40 80 176  2.10 420 788  3.80 760 1400 
0.50 100 212  2.20 440 824  3.90 780 1436 
0.60 120 248  2.30 460 860  4.00 800 1472 
0.70 140 284  2.40 480 896  4.10 820 1508 
0.80 160 320  2.50 500 932  4.20 840 1544 
0.90 180 356  2.60 520 968  4.30 860 1580 
1.00 200 392  2.70 540 1004  4.40 880 1616 
1.10 220 428  2.80 560 1040  4.50 900 1652 
1.20 240 464  2.90 580 1076  4.60 920 1688 
1.30 260 500  3.00 600 1112  4.70 940 1724 
1.40 280 536  3.10 620 1148  4.80 960 1760 
1.50 300 572  3.20 640 1184  4.90 980 1796 
1.60 320 608  3.30 660 1220  5.00 1000 1832 
 
STATUS LEDS 
   Each thermocouple input has a status LED.  It will be lit whenever an open condition is 
detected. If a thermocouple is plugged in but th e LED is still on then the thermocouple has an 
open short somewhere in it and must be replaced. 
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SERIAL OUTPUT 
   The serial output can be used for data logging when an EFI system is not accessible. To run the 
data stream, a RS-232 (DB-9) Fema le Receptacle must be purchased. 
12345
6789
 
 
Wire View of RS-232 (DB-9) Male Plug 
 
   Two wires need to be connected to a RS- 232 serial port. The YELLOW wire from the AEM 
thermocouple amplifier shall be connected to Pin  #2 (RX) on the serial port for receiving data. 
Pin # 5 (GND) on the serial port  is the ground and should be conne cted to the Blue wire. If a 
standard 9-pin serial cable is to be cut instea d, the (RX) wire is typically RED and the (GND) 
wire is typically GREEN. However, this should be confirmed with a continuity tester before 
attempting. 
 
   Use HyperTerminal for testing the data stream . This software is found on most PCs. To find 
HyperTerminal go to: Start | Al l Programs | Accessories | Comm unications | HyperTerminal. 
Name the New Connection and click OK. Set the COM port to the one being used\
 and click OK.  
 
Bits Per Second = 19,200 
Data Bits = 8 
Parity = None 
Stop Bits = 1 
Flow Control = Hardware 
 
   Verify the settings above and click OK.  When power is supplied to the AEM Thermocouple 
amplifier, temperature data will be displayed, as shown below. 
 
Junction Temp, Temp1, Temp2, Te mp3, Temp4 (in degrees C)  
 
 
AEM Inc. 2005 
Thermocouple Amplifier 
Version 1 
 
23.1, 122, 255, 700, 390 
23.1, 122, 255, 700, 390 
23.1, 122, 255, 700, 390 
23.1, 122, 255, 700, 390 
23.1, 122, 255, 700, 390 
23.1, 122, 255, 700, 390 
Data logging with HyperTerminal 
 
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SPECIFICATIONS 
Laboratory Grade Accuracy, 4 Channel K-Type Thermocouple Amplifier 
 
•  Works with any K Type Thermocouple 
•  Uses commonly available miniature thermocouple connectors 
•  On board cold junction temperature compensation 
•  0 to 1,000C ( 32 to 1,832 F) measurement range 
•  Can measure up to 20C degrees be low cold junction temperature 
•  0-5v analog output (x4) 
•  RS-232 serial output also included 
•  Fault LED’s tell the user wh en a thermocouple is faulty 
•  High quality Deutsch connector 
•  Includes mating harness 
 
Four Channel Thermocouple Amplifier 
Supply Voltage: 9 to 18 Volts 
Supply Current (nominal): 0.25 amps 
K-Type Thermocouple Inputs: 4 
0-5v Analog Outputs: 4 
RS-232 Serial Outputs: 1 
Minimum Measuring Temp: 20C Belo w Cold Junction Temperature   
Maximum Measuring Temp: 1,000C    
Harness & Connector Temp Limit:120 C 
 
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12 MONTH LIMITED WARRANTY 
 
Advanced Engine Management Inc. warrants to the consumer that all AEM High Performance products will be free 
from defects in material and workmanship for a period of twelve (12) months from date of the original purchase. 
Products that fail within this 12 month warranty period  will be repaired or replaced at AEM’s option, when 
determined by AEM that the product failed due to defects in material or workmanship. This warranty is limited to 
the repair or replacement of the AEM part . In no event shall this warranty exceed the original  purchase price of the 
AEM part nor shall AEM be responsible for special, incidental or consequential damages or cost incurred due to the 
failure of this product. Warranty claims to AEM must be  transportation prepaid and accompanied with dated proof 
of purchase. This warranty applies only to the original  purchaser of product and is non-transferable. All implied 
warranties shall be limited in duration to the said 12 month warranty period. Improper use or installation, use for 
racing, accident, abuse, unauthorized repairs or alteratio ns voids this warranty. AEM disclaims any liability for 
consequential damages due to breach of any written or  implied warranty on all products manufactured by AEM. 
Warranty returns will only be accepted  by AEM when accompanied by a valid Return Goods Authorization (RGA) 
number. Credit for defective products will be issued pend ing inspection. Product must be received by AEM within 
30 days of the date RGA is issued. 
 
Please note that before we can issue an RGA for an Electronics System, it is first necessary for the installer or end 
user to contact our EMS tech line at 1-800-423-0046 to discuss the problem.  Most issues can be solved over the 
phone.  Under no circumstances should  a system be returned or RGA requested before the above process transpires.  
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