How to Check Honeywell HPM Loading

N

Thread Starter

Nisar

we are planning to upgrade 65 pneumatic controller to DCS Controller & 65 loops shall be equally distributed in 3 existing HPM. Now my concern if you add these I/O do you think we will face any loading issues?
below is the Existing data of 3 HPM. please suggest.<pre>
UCN 4 NODE 17 HPM
CPU Free Percentage
CPU MIN CPU MAX CPU AVG
COMM 4.6 94 51 COMCF..
CTRL 72.2 98.5 84.8 CTLCF..

UCN 4 NODE 19 HPM
CPU Free Percentage
CPU MIN CPU MAX CPU AVG
COMM 5.6 94 48.11 COMCF..
CTRL 73.9 98.5 84.3 CTLCF..

UCN 4 NODE 23 HPM
CPU Free Percentage
CPU MIN CPU MAX CPU AVG
COMM 10.1 71.3 48.1 COMCF..
CTRL 76.6 91.4 86.5 CTLCF..</pre>
 
I see all CPU CTRL loading average are around 85%. For best practice, the average CPU loading of HPM is 75% - 80%.

During HPM node configuration, usually the engineer calculated and configured the HPM maximal loading so that users cannot configure the HPM more than 80% CPU CTRL capacity. He or she kept 20% of HPM loading free to acomodate alarms, events, messages, etc.

I suggest you do not add more points in the HPMs.

According to my experience, some Honeywell customers experienced HPM overloading due to this case. It happened especially when a lot of alarms or events arise.
 
Aren't the indicated numbers CPU FREE percentages ?

In that case the average load is currently only 20% in stead of 80%
 
Thanks Rudi. Yes, you're right. I was not careful to see the data. So there is still enough room to add more points into HPMs.

I suggest to determine processing and memory capacity of HPMs due to the additional points. Please refer to HPM control functions and algorithms in KB. It will help you to do good engineering and prevent HPMs overload. I know that Honeywell has XL spreadsheet to do this task, but I am not sure if they will give it to you.
 
Top