E150 Display power source

[308guru]

I've been connecting my E150 displays to FX plcs with the RS422 cables. I have also been supplying the 5V DC through it's power connector and from a 5V DC power supply. I happened to notice today that the display stayed powered up even when I removed the 5V power connector. So, my question is: Does the display receive power from the PLC via the RS422 cable? Am I doing something bad by providing power via the 5V connector too? They are all working flawlessly so far. Thanks.

[Sergei Troizky]

I am not familiar with E150, but older MTA10/12 did receive 5V power from the PLC via the RS422 cable.

[Rodney]

I have recently done a project with an E100 and it did receive its power from the P.L.C via the RS485 port. Rodney

[Paul416]

I can confirm that all the smaller E-Terminals (E50, E100 & E150) use 5v from the PLC. I have also ran them with the Mitsubish 5v PSU connected at the same time and had no problems.

[Crossbow]

You can use the internal 5VDC power supply of the PLC to power the screen. But two things to be careful of. 1. Make sure you've still got enough 5VDC for any extension modules you have on the PLC. 2. Mitsubishi warns that the 5VDC power supply to the serial port may not always be 5VDC. Sometimes it only comes up about 4.8, and that won't power up an E-terminal. Mitsubishi sells a cable (CAB DC24-5V) which converts 24VDC to 5VDC which has bare wires on one end (for the 24VDC powe supply on the PLC or external) and the round plug for the E-terminal on the other end.

[308guru]

So powering the 5V DC in AND using the serial cable sounds like the best bet. I've got a stand alone 5V power supply I'm using to power the display and a barcode scanner. It just seems weird to bring power in from two places.

[mjrx]

I've used lots of E150's on various projects and never connected the external power connection and never had any problems.

[Paul416]

I would say, take the power from an external source if u can. I have powered them both ways, and both at the same time, but its got to be better if u can power them from an external source, incase the PLC needs expanding at a later date. Just a word of warning, when the E50 First came out I used a bog standard 5v psu to program them, fried several of them. Dont know why? was a regulated 5v psu. Ended up buying a mitsi one, cost bout 15quid and was identical to what i had (even put it on a scope) Bizarre......

[Crossbow]

I can post the actual notice i received from Mitsubishi if anyone cares to read it. I too have used E150 in projects where it was powered by PLC port, but the E150ET (E150 with built in Ethernet) requires more 5VDC than the PLC can put out, so it requires the external power supply.