12-08-12, 11:24 AM | #1 |
Lex Parsimoniae
Join Date: Feb 2009
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Found a new current sensor
I love these Veris sensors.
http://www.vikingcontrols.com/_docum...oduct/H720.PDF The model 720 has an analog current output. Stick a 250 ohm resistor on the output and it will give you 1 to 5VDC for the ADC input on your micro controller. They can be found on Ebay sometimes.. Veris Industries Hawkeye H720 Industrial Accuracy Analog Current Sensor | eBay Seems like the 720 would be a reliable way to monitor heat pump power use..
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12-08-12, 07:16 PM | #2 |
Master EcoRenovator
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Cool, the controller will have to have a high enough sample rate to have accuracy to give good report.
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12-08-12, 08:04 PM | #3 |
Lex Parsimoniae
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Not sure, but there maybe some lag in the DC output. Since it can oddball frequencies
10 to 80 Hz, I'm wondering if you might even be able get away with sampling once every two seconds.?. One of the specs shows: Response Time 2 sec. This one needs a 12Vdc 30mA DC power supply, so it can supply up to 20 mA of current to the controller (or simple analog amp meter). That Span adjustment pot seems like it might be controlling the gain of an internal Op-amp..?. I might be able to set it so that 0 to 5Vdc output would be equal to 0 to 50 amps.. Make it easier to set up a simple volt meter display or save on programming in the acquisition & display controller program. Just calibrate it with the old Sears clamp-on AC amp meter and a DC volt meter. Sensor Power 12-30 VDC, 30 mA max. Amperage Range 0 to 200 A continuous Insulation Class 600 VAC RMS Output 4-20 mA Zero Adjustment 3.5 to 4.5 mA Span Adjustment 20 to 200 A, full scale Frequency Range 10 to 80 Hz Temperature Range -15°to 60°C (5°to 140°F) Humidity Range 10-90% RH non-condensing Accuracy 0.5% (combined linearity, hysteresis, and repeatability Response Time 2 sec Terminal Block Max. Wire Size 14 AWG Terminal Block Torque (nom.) 4 in-lbs (0.45 N-m) Agency Approvals UL 508, E150462
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My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less.. Last edited by Xringer; 12-08-12 at 08:12 PM.. |
12-14-12, 09:03 AM | #4 |
Lex Parsimoniae
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