SuriSarat

I am using the HSC0 of the ML1400.  Using an hengstler incremental encoder RI58-O/2000EK-42KD 2000 PPR.  Need this encoder to ascertain the position of the Wheel rotating. I am using a Proximity sensor, rotating the wheel at slow speed and finding the 0 / 360 degree position of the wheel. When the prox. sensor is sensed, I move 0 the ACC Tbe encoder has A, B ,N and I have wired A,B to the PLC.  I want to determine the degree of the wheel rotation. All seemed to be working fine for 3 days. Suddenly we feel the encoder is missing pulses. Following is the settings of the HSC  PFN 3, UIE 1, FE 1, AS 1, CE 1, SP 1, UFM 1, OFM 1, OFI 1, UF 1, OF 1, MD 1, CD 1, CU 1, MOD 3, HIP 2000, LOW 0,  OVF 2000, UNF 0  I AM USING THE INTERRUPT (PFN 3) to count the encoder revolution (cycle) by incrementing a integer variable.  How I feel that we are missing pulses as follows 1. We are using the encoder position (angle 2000 pulse = 360 degres, 1 pulse = 360/2000 (0.18).   2. Based on angle we use a solenoid to blow air. This works well for a few cycles and then the angle changes. To verify, I used the proximity sensor input to verify the HSC Accumulator as follows if the proximity sensor is on and if the HSC 0 ACC < 1950 add 1 to a variable (This add is just to track )  After around 60 revolutions, the value in the variable starts accumulating.    Now my query is : Should I use MOD 4 as it is two wire. If I use the N channel the encoder resets erratically (probably my configuration of the HSC is wrong) I feel I am making a mistake in the configuratoin above. Can someone please help and through some light. Thanks        

Just one more thing. I am using  LAD 3 (given as PFN 3 for the HSC0) to increment a memory variable. Apart from the above PLS requirement, where I want to switch on outputs based on the HSC accumulator value, I also want to keep count when the ACC reaches HIP of 2000 set in the Function file of HSC. You have just set HIP as 0 in the function file / HSC 0 area. I wonder if your PLS setting and counting of the encoder cycle can be done at the same time.   

Thanks mpereira. I downloaded your example. Will test that today and post my comment. You have set your HIPs in your PLS file as follows 500 -->  OUTPUT 0 ON 150--> OUTPUT 1 ON 150 --> OUTPUT 2 ON 200 --> ALL OUTPUTS OFF You started with 500 (reverse order). Was this intentional. I mean do we have to give in descending order for the PLS to work ? Also in above settings, why can you not switch on both Output 1 and Output 2 at the same time against the 150 HIP ? Will not both outputs switch on at the same time if given in single line ? Also , you have not used the OLD part. This is because of the TIP in the manual as follows :  The Output High Data (OHD) is only written when the High preset (HIP) is reached. The Output Low Data (OLD) is written when the low  preset is reached. TIP  Output High Data is only operational when the counter is counting up. Output Low Data is only operational when the counter is counting down. In another 5 hours time I will try this and update here. 

PLC Micrologix 1400 with 6 HSC. Connected an encoder with A,B & N. The encoder (Rotary incremental) is 2000 pulses per revolution 1.  Need to achieve the following : 1. Whenever 2000 ppr reached increment count as 1 cycle complete 2. When 250 PPR then activate a solenoid Output (O0/0) 3. When 1750 PPR turn of output in step 2 I connected the Encoder to HSC0. Set the HIP to 2000 and LIP to 0. Then I created a Program File No. 3. In this I do the add of count (increment) . The PFN 3 is raised successfully on each 2000 PPR reached (as interrupt style). Now when I use the PLS feature, I set the HSC0 Mode as A00 (as per the example in the manual) . In the PLS I set the HIP to 250 , OHD output 0 as 1. I set another HIP to 1750  and set OLD output 0 to 0.  In the function file HSC0, I set the OMB to 1. With all this done, I get the following issues 1. Output 0 not coming on and off as needed in step 2 and 3 above 2. Now the count increment happens almost 2 times. First 0 - 250 and then 0-1750. How to address this problem. Where I am going wrong ? Thanks in advance. S.s