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kcor

allen bradley encoder 845t-dz33acn

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Have one of the allen bradley 845t-dz33acn incremental encoders, and trying to find a connection diagram for it on ab site. Maybe, just not familiar with the ab site, but tried searching the knowledge base and manuals, but no luck. Is there a quick start, manaul etc. for this encoder thanks

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Trying to figure out how to wire this encoder into a micrologix 1200. Have one of the encoders that came off a old machine, but connection diagram.

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Here is a page from the 1769-HSC about wiring the 845H encoder. Maybe this will help. What are you wiring it into on the 1200? 1769_HSC_Page_61_Encoder_Wiring.pdf

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I am not sure about MLX1200 connection, but here is full encoder info http://literature.rockwellautomation.com/i...ca500_-en-p.pdf Edited by Contr_Conn

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Pin B to your +24 Pin A to your DC Common Pin E to Input 0 Pin D to Input 1 Input 0 and 1s common to your DC Common Pin C, the Z marker does not get connected If the encoder is counting backwards from what you want swap the wires going to Input 0 and 1 Don't use the internal 24VDC to power the encoder. Use an external power supply. Actually I suggest this for all connections to the Micrologixs I know you pulled this off of a machine but in the future make the option C a 6 instead of a 3. They work better over longer distances Sample program http://forums.mrplc.com/index.php?showtopic=7960 Before looking for an error in the program make sure both the Input 0 and 1 LEDs are flickering That's all I can think of, enjoy TW

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ENCODER_CAMs_AND_SCREENS.RSSThanks Hooked the encoder up on a 1200 that I had and a panelview 300, attached program and tried to put comments explaining.

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Did it all work?

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No problem. I'm a little busy tonight, but check back and I'll try to look at your program a little closer for critique. TW

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The only thing I see you may want to add is an RAC instruction to set the encoder ACC value to a particular number at power up or off of a switch

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Trying to run it on the bench, and this is what is happening. I have a L40BWAR Micrologix 1200, it has 24 inputs, and 16 outputs (relay) When I turn the encoder, the output on the output side of the LIM instruction turns on when the encoder value is between the low and upper limits. Now this is the wierd part, as long as I am turning on outputs 0, 1, or 2 everything works fine, but if change and try to turn on output 3 or higher, when monitoring with the laptop, you can see the output, for example the lim is set to turn on output 3 if value of encoder is between 200 and 300, when encoder is between 200 and 300, when monitoring, the output 3 will turn green, but the output light on the plc will not turn on. I can force that output on, and it will turn on at the plc and the light on the plc for that output will turn on. Wierd, I called my ab rep and he is confused as well. I even went in and added a rung that if a certain input is off, which it is all the time, turn on output 3, same thing, it will show on the laptop that it is on, but the light on the plc will not turn on, but i can force it on. Any thoughts on what I may be doing stupid

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Can you post your latest code that shows output 3? Nevermind on posting the code. Goto your HSC function file and scroll down to the OMB (Output Mask). You have it set at 2040 which gives the HSC controls of outputs 3-10. You are doing your output control through the ladder. Set the OMB to 0 and it will work fine TW

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Thanks alot TW I have been trying to figure it out for the last 30 minutes. Emailed the file to ab tech support about a hour ago, and still not heard from them yet. thank goodness for this site. I guess I tried to jump in and do it without reading everything on the HSC To be honest, will read more about it tonight, but do not remember reading anything about that. Too big of a hurry, suppose to go to South Carolina tomorrow and install it on a machine. Just goes to show, read the instructions over and over. Thanks

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Change you MOD to 6. This is the same as 7 except removes the external hold and reset inputs. If you need another input you will pull your hair out trying to figure out why your encoder quit working when you add something to input 2 or 3. Good Luck TW

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Thanks Plan on reading up on the HSC later tonight. I am using input 0,1 and 2 The encoder is a - a,b z type encoder Input 2 is the z input.

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Yes if I had read Ladder 2, Rung 0's comment I would have seen that. Might change your comment to say input 2 instead of 3 and label them your Inputs even though they are not used in the program. You've got Descriptions for your inputs from another program. It will help years down the road when you can't even remember which PLC you have in it

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Thanks TW That was a generic program that was already loaded into the plc, I just tried to quickly add the HSC and encoder to test it on the bench. going to make another post that maybe you have some experience on.

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ENCODER_t.RSSOne more question- is there a way to clamp the HSC accumulator value so that it can not go below zero. Accumulator value goes from 0-10000, then if I turn encoder backwards, goes from 1000 to 0, then will go to negative numbers -1 to -1000. I tried clamping it, but did not work. Any advice Thanks

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What do you want it to do when it turns backwards? Not count or count down to 0 then stop?

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ENCODER_T_PANEL.RSSTestScreen4.PVAI was trying to see if I could get it to not count backwards, figured out what I was doing wrong. Have connected a panelview micro 300 on the bench (suppose to take and install tomorrow), and I wrote some test screens for the bench, and on the main screen I placed a multistate indicator to indicate when the glue gun output was firing. What I noticed is that if I turn the encoder slowly by hand on the bench, the indicator will change states to indicate that glue is on, but if I turn it quickly, the output on the plc will come on and off, before the display can change states to show that it turned on and off. Is the micro 300 just that slow in response time, or am I overlooking something.

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I'm going to say the slow response time. There not really a way to set the polling rate. Is this a DF1? What type of times are we talking about here.

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TW Not going to display that on the screen. It is a very quick signal, packaging machine is running about 60 packages per minute, not sure exactly how fast the encoder is turning, but it is pretty quick, so at the moment, not going to show it. Have another question, hate to ask for something outside of allen bradley on a ab forum, but just called my ab rep and got a price on the encoder and cable, and it is $525. Would you happen to know of another type that would work just as well. To do 9 machines can eat into a budget very quickly. thanks

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Any encoder with a Push Pull or preferably a Differential Line Driver Output of 24VDC will work. I can tell you that the AB is a good encoder. We used to use Dynapar and did not have good success with them, then their support was not awful when we went to them about some DOAs we had. I wouldn't suggest them for anything, too light for a boat anchor. Now down dirty and cheap, Automation Direct carries one. I think it is a Sick encoder but can't remember. Omron used to have a really inexpensive one but I was looking for it a few months ago and couldn't find it. Omron may have discontinued it. What was the resolution? Do you want a cable or a connector? Whatever brand you decide post it here so we can verify the output type will work.

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Thanks TW I called my ab rep back and told him that the price was not very good. They worked on the price, actually reduced it enough that I went ahead and ordered two as well as a couple of the panelview 300

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That's great. Glad it all worked out

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