Programming options on EEZ H24005 PSU - Page 1
Forum section: electronics / beginners

author: cs.dk
author_rank: Unknown
timestamp: February 11, 2018, 10:10:26 am
content: First of all, I know next to nothing on programming. And I'm not even sure the PSU is capable of this exact output-style.Is it possible to program the PSU to mimic a lambdasensor?I have a car with a fault, maybe broken wires, maybe bad fuel/air mix. I can't see the lambdavoltage on the tester, and a multimeter confirms that the lambdasensor is giving a very low voltage (20-40 mV) output. Maybe the sensor is trying to drive a short? However the MOT 4-gas analyzer shows a fine lambdavalue when the car is tested. (High CO and HC value, because the ECU thinks it runs lean, and adjusting up accordingly)If I could inject a lambdasignal right to the ECU, i should be able to see it on the tester, if the ECU's inputs are not dead. And the car should react to it.The signal is something like this;

author: prasimix
author_rank: Unknown
timestamp: February 11, 2018, 11:13:22 am
content: It looks like a sinewave that is around 1 Hz. That is achievable with LIST SCPI commands. Establish connection via USB or Ethernet and send the following commands one by one:Code:list:coun inflist:volt 0.50, 0.53, 0.55, 0.58, 0.60, 0.63, 0.65, 0.67, 0.69, 0.70, 0.72, 0.73, 0.74, 0.74, 0.75, 0.75, 0.75, 0.74, 0.74, 0.73, 0.72, 0.70, 0.69, 0.67, 0.65, 0.63, 0.60, 0.58, 0.55, 0.53, 0.50, 0.47, 0.45, 0.42, 0.40, 0.38, 0.35, 0.33, 0.31, 0.30, 0.28, 0.27, 0.26, 0.26, 0.25, 0.25, 0.25, 0.26, 0.26, 0.28, 0.30, 0.31, 0.33, 0.35, 0.38, 0.40, 0.42, 0.45, 0.47list:curr 0.05list:dwel 0.0164trig:sour immoutp 1init*trgSet current is 50 mA, and "dwell" time is 16.4 ms (i.e. 1 Hz / 61 is ~16.4 ms) You should get something like this:Unfortunately we still don't have a simple way of creating "function generation". Therefore you have to use an external application for doing that. Please find in attachment .ods file (converted to .xls too) that is used to generate list of voltages (column D) with desired amplitude (cell D1) and DC offset (cell D2). Number of points is 61 but with current firmware version it could go up to 256.If voltage precision is not enough you can do the following: define 10x higher amplitude and DC offset and use voltage divider to set it back to needed level. In that case you have to replace voltage list with the following statement:Code:list:volt 5.00, 5.26, 5.52, 5.77, 6.02, 6.25, 6.47, 6.67, 6.86, 7.02, 7.17, 7.28, 7.38, 7.45, 7.49, 7.50, 7.49, 7.45, 7.38, 7.28, 7.17, 7.02, 6.86, 6.67, 6.47, 6.25, 6.02, 5.77, 5.52, 5.26, 5.00, 4.74, 4.48, 4.23, 3.98, 3.75, 3.53, 3.33, 3.14, 2.98, 2.83, 2.72, 2.62, 2.55, 2.51, 2.50, 2.51, 2.55, 2.62, 2.72, 2.83,2.98, 3.14, 3.33, 3.53, 3.75, 3.98, 4.23, 4.48, 4.74This time you'll get this (and don't forget to apply voltage divider!):

author: cs.dk
author_rank: Unknown
timestamp: February 11, 2018, 11:55:07 am
content: Thanks a millionThe voltage precision should be fine, it's not that critical.I'll have to read this chapter, to see how i transfer the commands to the PSU;http://www.envox.hr/eez/bench-power-supply/psu-scpi-reference-manual/psu-scpi-introduction.html

author: prasimix
author_rank: Unknown
timestamp: February 11, 2018, 12:07:52 pm
content: It's a very simple: use any serial comm (for USB) or telnet (for Ethernet) console. Former one could be also so-called "Serial monitor" that is included in Arduino IDE. Later one could be PuTTY or command line "telnet" (depends of your OS). For telnet (i.e. Ethernet connection) you have to select port 5025 and IP address of the PSU (you need to activate Ethernet in EEZ H24005 system settings and restart it). Then simply start telnet session with:telnet <ip_address> 5025

author: cs.dk
author_rank: Unknown
timestamp: February 11, 2018, 02:09:30 pm
content: Great, i'll give that a goHowever, Ethernet seems to be dead on my device - No LED indicators, and no IP-adress. Will have to look further at this.