High Speed ION Module - 1/2 cycle measurements - ION 8650

[rodrigorpgsc]

Hi,

We intend to get slow AND also fast measurements at our ION8650. We need request this data at real time and using modbus TCP table.

We configure a PLC to act as modbus master and request data each 60ms. So we are able to read VLL avg scaled(address-40184) and kw tot scaled (address-40204), although the meter answer each of our request this values only update at each 1s.

This measurement, at 1s rate, is very good for revenenue measurements because don`t show noise. However we would like to know how to read faster measurements too, even with noise.

I read the manual a lot and sounds that 8650 allow to measure1/2 cycle (instantaneous measurements). This fast measurement is allow to be request at modbus interface? How to configure 8650 to do that?

[Charles_Murison · Accepted solution]

Hello @rodrigorpgsc ,

You are correct that the ION8650 meter does have some modules that update at a 1/2 cycle rate and other modules that update at 1 second and very few that can be either. The modbus slave modules (used for modbus communications) is a module that only updates once a second regardless of what inputs are connected. There is no way to retrieve data from the meter via modbus any faster than once a second.

The protocol DNP can update at the 1/2 cycle rate, but only for a few measurements as configuring the module for 1/2 cycle uses a significate amount of CPU power.

Regards,

Charles

[rodrigorpgsc]

Charles,

Thanks!

We`ll try to request using DNP protocol for 1/2 cycle.

[rodrigorpgsc]

5 variable using 1/2 cycle update time and DNP3 sound ok or is too much for CPU ?

[Charles_Murison]

Hello @rodrigorpgsc ,

The DNP module itself is not a standalone item. The total CPU usage is also dependent on the rest of the framework on the meter. For example if you do not need EN50160 there is a bit of CPU usage you could save CPU "space" by removing the modules that support EN50160.

DNP modules can have up to 4 inputs. If trimming down to 4 measurements is an option that would be easiest. If 5 measurements are a requirement then 2 DNP modules needed. The DNP module at 1/2 cycle update times will use the same CPU usage with 1 measurement linked as 4. Just to keep this in mind when selecting measurements.

Regards,

Charles

[rodrigorpgsc]

Hi Charles,

Thanks (a lot) for your patience

I logging at 8650, using SCH ION setup, and find 34 (`slow`) points at standard DNP map, so the standard map is using 9 dnp modules by standard, don`t?If I don`t erase the default and insert 5 points I`ll use 10 dnp modules, don`t?

The rigth place to configure the export of HS is at (I attach a screnshot)

Ion setup->3rd party comm->DNP map setup ->dnp register ->Parameter selection

?

I intend to select a HF variable, ex: HS PF lead tot, and put at map to allow my PLC to begin request to request this fast variable

[Charles_Murison · Accepted solution]

Hello Rodrigo,

Using ION Setup DNP wizard to setup the DNP could work but may hide some elements from you. I would put meter into advanced mode, add the module, link registers and configure registers manually. This is not a simple task which is why the wizard in ION Setup exists.

Regards,

Charles

[rodrigorpgsc]

Thanks Charles!

I'll do that.