Dynamic Metering with ION Meters

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ION meters are capable of providing dynamic metering solutions for unique installations because they are very flexible and customizable. A few examples are:

• Net Generation: dynamically applying transformer losses between multiple meters on the low side of a transformer.
• Load sharing: totalizing the auxiliary loads that are shared between generators.
• Dynamic reporting with battery energy storage system: monitoring a renewable energy resource and ensuring that charging station is only billed when supplied by the utility, and not when self-supplying from the main generator resource.

ION meters can function like a lite RTU using Modbus Master protocol serially or over Ethernet.  They can also monitor analog and digital inputs based on meter model.  This provides the meter with a lot of flexibility in monitoring other devices and loads, and it’s not limited to only other ION devices.  Being able to centralize the totalized data in a single meter, you can create 1 load profile to reflect the net energy usage, and the local energy usage is still available in each device.

Dynamic Metering frameworks allow you to use the power of the ION meter to simplify the number of meters that need to be read for billing, allocate losses based on individual usage, and split loads amongst feeds accurately!

What is needed to setup a dynamic meter system?

1. Totalizing Meter (ION 8650A/B, ION 7400, or ION 9000)
2. Monitoring device for each load or feed, which supports Modbus.
3. Reliable communication path (ethernet or serial) between devices.

Advantages of Dynamic Metering Systems:

1. Provides a single data node for all required information utilizing the power and flexibility of ION meters!
2. Allocations are done in real time and reflect current loads rather than estimation or scale factors.
3. Meter contains information for net and individual loads on single device.
4. Using Modbus communications also provides status checks on data, and are direct reads from the device
   1. Communication Status monitoring provides events so you know when communication is lost with timestamp.
   2. Direct reads have no conversion factors as the device is read directly rather than converting a signal to determine the load.

You will find 3 examples of dynamic metering schemes in the following pages:

Example 1: Net Generation

In this example we have a generator meter and the main aux meter. This scheme can be used to calculate the net power and energy.  You can also calculate the net current at the low side of the GSU and then compensate to the high side of the GSU.  Once you’ve done this you can setup the load profile to reflect net and/or individual energy measurements.

Example 2: Load Sharing

In this example we have a power plant with 2 generators and auxiliary loads that feed shared and unitized loads. Thanks to the flexibility and customization capability of ION meters we can split the shared loads between units based on generation and weighted splits between unit.  We can then calculate net power based on gross, unit aux, and an accurate portion of the shared loads.

Example 3: Dynamic Reporting with Battery Energy Storage Systems

In this example, the goal is to monitor charging and discharging of the battery energy storage system (BESS) and know when it’s being charged by the system versus when it’s being charged by the site’s generation resources.  With this information we can disable recording in the BESS meter when it’s being self-supplied by the site so that its recorder only reflects energy used from the substation to charge the battery.  This setup also provides the option to apply transformer losses on the generation site meters to the high side of the GSU transformer.