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7

The connector and the PCB itself gives some hints: The frontside of the IR-PCB(lower left in the picture) has a lot of LEDs exposed and one optically shielded from the other(down in the middle). This is an indicator that there is some measurement happening on a single IR LED and thus there is at least one wire carrying this signal. Another hint is the ...


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The given micrologix seems to have relay outputs, rather than sourcing outputs: This means that in order to power your sink devices, you need to supply voltage separately to the VAC VDC Pins. Connect the DC OUT + from the input terminal block to VAC VDC in the 15th pin of the output block. Next, connect one terminal of the LED to the O/5 terminal and the ...


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Since I cannot answer in the comments I'll add some little tips. About the wiring, if you don't want to bother with calculation (usually better but some quick answer might be sufficient), there is some web calculator that I found well designed: circuitcalculator. When you define your wire size, take around 20% margin of your wire max current as a max fuse. ...


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simulate this circuit – Schematic created using CircuitLab Figure 1. A possible solution - but it relies on RLY2 having a much faster drop-out than RLY3. How it works: Mains on RLY2 is energised. RLY3 just repeats the operation of RLY1. Mains drops out If RLY1 was off then RLY3 will be off and will not change state. If RLY1 was on then RLY3 will ...


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Here's how you would need to wire it.


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Since you don't hear any relay clicking to match the output LEDs it seems as though the relays are not picking up. The relays may be powered by a separate voltage source than the logic which is likely to be 5 V. It's possible that part of the PSU has failed although I'd expect the PLC to indicate a fault in that case. Check the diagnostics page on the RS ...


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Looks like you need to wire 24V into the "VAC/VDC" terminal next to the output you want to control the light, wire the positive terminal of the light into the output terminal itself, and wire the negative terminal of the light to ground (COM or power ground, not earth ground). Edit: the manual states that the 24V out can only supply 250mA. Does ...


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Consider U2. It's a three input NAND gate. It's truth table is shown below. 13 1 2 Out ---------------- 0 0 0 1 0 0 1 1 0 1 0 1 0 1 1 1 1 0 0 1 1 0 1 1 1 1 0 1 1 1 1 0 Now consider: Does it matter which state pin 1 is in? Will the other pins have any affect on the output if pin 1 is high ...


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The wording is strange, but: all of these circuits implement a function \$F = f\left(A, B, C, D, E\right)\$. If two circuits implement the same function \$f\$, then they are "preserving the logic expression". When you build a truth table for a logic function, that truth table is enumerating the output of the function for each given input. If you ...


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There are really a lot of options here but most of them depends on the characteristics of currently used components. I'll throw a couple of 1st that came to my mind. Get a NC (normally closed) reed switch. And/or 3-pin NC/NO switch. The one that is normally closed means that it will conduct once the external magnet are moved away from it. Add a P-channel ...


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You should search for an "SPDT reed switch" These have three terminals: a "common" terminal, one that is connected to the common terminal when the magnet on the door is next to the switch (usually marked "N.O." for normally open), and one that is connected to the common terminal when the magnet on the door is away from the ...


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