Keyence Fiber optic units

Does anyone have experience using the Keyence Fiber Photoelectric Sensors?
I am trying to use a fiber optic light to sense product (sort of like a prox switch, but smaller).
The Sensor needs to be connected to a 24V sinking input on a Micrologix 1000.


I have the connection diagram for the keyence sensor.
It shows a 4.7K Ohm pullup resistor between the brown and the black wire as well as between the brown and the orange wire.

Where is a good place to buy these resistors? B&B?
Do you just mount them right to the terminal strips on the PLC?
Thanks for any input (No pun intended)
George Bradley

The pullup resistor is used to change the NPN output to PNP. Remember that this also INVERTS the sensor's output. IOW, a "dark-operate" sensor becomes "light-operate, and vice-versa.

You can get these resistors at ANY electronics supply (or Radio Shack if you have one in your area).

Personally, I'd rather see you buy the correct (PNP/NPN) sensor for your application, instead of using the resistor. Avoids questions like "Where can I put the resistor where it won't be vulnerable?". If the sensor is ONLY available as an NPN (which Keyence likes to do), you can use their OP-5148 converter. It's basically just an expensive pullup resistor, but in a nice package...

beerchug

-Eric

P.S. Which Keyence sensor are you using? Part number?

Not very true Eric,

if I am not wrong, most of the Keyence sensors have both configurations. For PNP ones the model number have a 'P' suffix.

For eg. FS-V20 for NPN
FS-V20P for PNP

The model that I am using is the FS2-60
but the equivilent new sensor is the FS2-V20

Caution: Rant Ahead...

Yes chavak, Keyence IS now offering most of their their sensors in both versions...

This was not true in the beginning though. I had used Keyence a few years back and all the sensors I needed were only available in NPN versions.

A few of my 'thoughts' on Keyence...

I have recently started using more Keyence photoelectric sensors, but am not impressed. Low cost yes, so I guess you get what you pay for?...

I use quick-disconnect cables on everything, so one of my biggest grips is their use of FOUR-pin M8 connectors on the PZ series. 3-pin M8 connectors are pretty standard in my neck of the woods, so I always have to remember that when using PZ sensors, I have to get 'special' cables so they can have their dopey 'light-on/dark-on" wire. If they don't have room for a light/dark switch on the sensor, can't they do something simple, like Omron does, and just flip the power wires for light/dark selection?...

Not to be harsh on Keyence, they do have some pretty neat stuff! And they're constantly coming out with new products, but so much so that I have trouble keeping up. I find something I want in the 'latest' catalog, only to find it has been replaced by a newer item, so I have to dig through the pile of 'new product' leaflets that (seem to) come weekly. My concern is that something I put on a machine today will not be available when it needs replacement. Sure they may have an equivalent unit, but will it mount the same way? And will the customer need to learn a new adjustment procedure?... utoh

George's last post emphasizes this point... The FS2-60 has been replaced by the FS2-V20. The FS2-60 is in the latest catalog, so I go to the Keyence website to download a manual so I can help George out. Hmmm, no manual there. Only a link to the 'new' FS2-V20 manual. I just went through the same thing with an LG-81 Laser Gauge. A customer asked us to put one on a machine we're currently building, as he has this unit on other equipment and is familiar with it. It's in the 'latest' catalog, yet the website says the LK-81 is an "old model", and recommends the LK series instead. Old? It's in the 2003 catalog, and it's currently 2003! Ok fine, I check out the LK series. This is a C-O-M-P-L-E-T-E-L-Y different sensor than the LG series, even requiring a seperate controller.

So what do I do? Right now, I can still buy an LG sensor, but what about a year from now when someone runs into it with a forklift? Normally, the customer could just swap out the unit and go, but if the only replacement is an LK unit, it's not so easy. First off, where is this new 'seperate controller' going to mount? And where's the 'GO' output that the LG had? Now we need to change the PLC program as well.

Who's doing (and paying for) these modifications? I'll bet it ain't Keyence!... mddr

One other gripe... It's probably just me, but their catalog is thoroughly confusing to me. Too much info packed into too small a space. And why does it need to be 7-1/2" x 10"? Is there something wrong with the 8-1/2" x 11" 'standard' catalog size?...

To get back to George's topic...

You can put the pullup resistor(s) across the BRN and BLK and/or BRN and ORN wires, or use their NPN/PNP converter, or exchange your sensor for an FS2-60P (if they still sell them). Personally, I think Keyence should exchange your 'antiquated' FS2-60 for an FS-V21P, but first make sure it will fit (physically) in your application (The FS-V20 series is bigger then the FS2-60!)... :nodi:

beerchug

-Eric

Personally, I think Keyence should exchange your 'antiquated' FS2-60 for an FS-V21P

Click to expand...

Yes my Boss purchased the unit about a week ago. I don't know why the sales person didn't sell him todays product.

Here is the connection diagram.

Sorry about the large Jpeg.
If I go ahead and use this amplifier, do I need install both of the 4.7K ohm resistors?

You only need the pullup on the output you're using. I doubt you're using the "alarm" output (orange wire), so you'll only need it between the black and brown wire.

beerchug

-Eric

Thanks Eric
I'll let you know how it goes.
G Bradley