I was not able to find any info about Opta min/max current draw or power consumption. The technical data lists only that all three Opta models need 12 to 24V power supply. But what power/current capability is required? I am not interested on guesses or rough estimates.
I have a power supply with a amp meter. At idle it draws 45ma. With one relay pulled in it draws 68ma.
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Oh and at 14 volts.
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Thank you for doing the tests/measurements. Which Opta did you use for tests (Lite/RS-485/WiFi)?
The Opta RS485 on my bench is drawing 34mA at 24.0VDC, with Ethernet/TCP/MQTT activity, no USB connected, no outputs on, and no RS485 running.
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Thx for feedback! That evaluates to 0.8W.
Interesting would be also to know how much a relay of Opta draws. Could I ask you to retest with a relay activated. Thank you!
@xrk, My Opta is occupied with other tests, but @plctech measured a 23mA difference at 14V when a relay was on, so ~320mW/relay.
I wonder if with 24V supply, the relay current might be different, as most often in electric circuits relay power rail is not voltage controlled.
@xrk, relay voltage needs to be consistent within a tolerance spec to ensure proper operation and to avoid overheating. So the relay current will be consistent. On a wide-input device like the Opta the relays will mostly likely receive power from an on-board regulated supply, such as 5 or 12V.
Oh, and section 4.2 on page 8 of the datasheet states the power consumption to range from 0.6 to 2.2W, which agrees nicely with 4 relays * .32W + 0.8W = 2.08W. The remaining difference is a non-issue and can be attributed to tolerances and CPU/peripheral activity.
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