AdvancedHMI Software

General Category => Open Discussion => Topic started by: Archie on June 08, 2019, 12:09:10 AM

Title: PLC Scan Time Benchmark
Post by: Archie on June 08, 2019, 12:09:10 AM
I posted this on another forum and found the results interesting so I thought I'd share them here. I ran a couple intensive tests on various PLCs to see how fast they could scan a program. The tests consist of a math and conversion, index text, bitwise test, and bubble sort. While running the code I checked the scan time to see how long it took the PLC to process it. Here are my results so far. Times are in milliseconds:


MathTest  IndexTest  BitwiseTest      BubbleSort
Omron CP1H
2030.0
2350
Schneider M340
849.0
411
32
---
2080-LC20-20QBB (Micro820)
499.0
744
---
---
Siemens S7 151-8 CPU
430.0
609
307
---
CompactLogix L16ER v24   
348.0
131
148
1398
CompactLogix L24ER     
293.0
ControlLogix L71 v31     
313.0
147
167
1570
AD Productivity P1-540
271.0
---
AD Productivity P2-550
264.2
---
Beckhoff CX8090
255.0
631
Click C0-11DRE-D
202.0
---
Omron NJ101-9000
84.0
11
82
ControlLogix L85E v32
9.5
3.5
2.4
77
Omron NX1P2-9024DT1
8.1
3.0
5.0
ControlLogix L85E v28
7.5
3.7
2.6
83
CompactLogix L306ER v32
7.3
3.4
2.4
78
Beckhoff CX9020 TC3
6.5
3.8
2.3
71
BrainBoxes BB-400/CodeSys 3.5.15
5.1
6.3
3.6
38
Beckhoff CX5140 TC3
4.2
11
Kunbus RevPi Connect+/CodeSys 3.5.14
2.5
3.1
1.8
33



Test Code in RSLogix Format
MathTest
Code: [Select]
Real1:=123;
Real2:=456;
FOR i:=0 TO 99999 DO
DINTResult:=(Real1*Real2);
END_FOR;

IndexTest
Code: [Select]
FOR j:=0 TO 9999 DO
  FOR i:=0 TO 9 DO
DINT1[i]:=DINT2[i];  (*'Arrays of 10 elements *)
  END_FOR;
END_FOR;

BitwiseTest
Code: [Select]
FOR i:=0 TO 99999 DO
DINTResult:=i AND 2730; (* '* Every other bit for 12 bits *)
END_FOR;

BubbleSort
Code: [Select]
Result[0]:=2;
Result[999]:=-1;

REPEAT
swapped:=0;
FOR i:=1 TO 999 DO
IF (Result[i-1]>Result[i]) THEN
Temp:=Result[i];
Result[i]:=Result[i-1];
Result[i-1]:=Temp;
swapped:=1;
END_IF;
END_FOR;
UNTIL (NOT swapped)
END_REPEAT;

Title: Re: PLC Scan Time Benchmark
Post by: bachphi on June 09, 2019, 03:53:45 PM
If I am not mistaken , RevPi is only 3B, not even 3B+ , yet it beat out  $16K L85E processor?
Title: Re: PLC Scan Time Benchmark
Post by: Archie on June 09, 2019, 04:24:21 PM
I did the test on a RevPi Connect+ , which uses the compute module 3+ that I think is the equivalent of the B+

I was surprised it was about 2.5 times faster the AB L8x processor (The latest quotes I got for power supply, rack, and L85E came in near $20k). I ran multiple tests with the RevPi as an Ethernet/IP slave to a CompactLogix and an EtherCAT master to Beckhoff IO. I even did some testing with it as a Modbus server communicating with AdvancedHMI. Handled it all with ease. For less than $500 for hardware and a CodeSys license, it really is a game changer.
Title: Re: PLC Scan Time Benchmark
Post by: larryhts on June 10, 2019, 06:24:15 AM
It would be interesting to see the Automation Direct P2-550 PLC or any of the Productivity Series PLC’s.
We are using them for our machines along with the Advanced HMI 10” TouchPanel.
Title: Re: PLC Scan Time Benchmark
Post by: Archie on June 10, 2019, 09:29:24 AM
Quote from: larryhts on June 10, 2019, 06:24:15 AM
It would be interesting to see the Automation Direct P2-550 PLC or any of the Productivity Series PLC’s.
We are using them for our machines along with the Advanced HMI 10” TouchPanel.
I ran the math test on a P2000 and added it to the results above. I'm not efficient at all with the editor, so I didn't convert the bubble sort. If you have time to convert the bubble sort to the ladder and post it, I can load it up and test it.
Title: Re: PLC Scan Time Benchmark
Post by: Archie on August 29, 2019, 11:19:13 AM
I added more to the list. The one I was surprised about was the L306ER CompactLogix. I did not expect it to be faster than the L85E ControlLogix
Title: Re: PLC Scan Time Benchmark
Post by: PLCGrub on March 26, 2020, 03:39:00 AM
Hi All,

Stuck in Isolation so what the heck

Just ran the maths on the P1-540 productivity 1000 with an average of 271msec,
and the Click C0-11DRE-D average of 202msec

Once I work out the other tests I will add those results
Title: Re: PLC Scan Time Benchmark
Post by: Archie on March 26, 2020, 10:43:08 AM
Quote from: PLCGrub on March 26, 2020, 03:39:00 AM
Just ran the maths on the P1-540 productivity 1000 with an average of 271msec,
and the Click C0-11DRE-D average of 202msec
Thank you for the additions. I added them to the list
Title: Re: PLC Scan Time Benchmark
Post by: PLCGrub on October 21, 2020, 05:24:37 AM
Hi,

I had a quick play with a 2080-LC20-20QBB (Micro820):

Maths Test - 499ms
Index Test - 754ms


Title: Re: PLC Scan Time Benchmark
Post by: Archie on October 21, 2020, 08:20:26 AM
Quote from: PLCGrub on October 21, 2020, 05:24:37 AM
Hi,

I had a quick play with a 2080-LC20-20QBB (Micro820):

Maths Test - 499ms
Index Test - 754ms
Thanks for the additions. I added it to the list.