ME237 panel three-phase multi-function power meter that supports direct current input or external open Roche coils or voltage CT
The ME237 supports three-phase, three-wire and three-phase, four-wire systems.
Realize line-free testing, simplify testing steps, and save construction costs.
The amount of electrical parameters collected at the front end is transmitted to the system data center in real time.
The RS485 communication interface is standard and is compatible with a variety of configuration systems via the standard Modbus-RTU protocol.
The current, voltage, power factor, harmonics, power, electrical energy and other electrical parameters on the A, B and C phase grids can be measured.Power Meter Characteristics
The power meter measures currents and voltages and reports real-time RMS values for all 3-phases and neutral. In addition, the power meter calculates power factor, realpower, reactive power, and more.
The following sections list the metering characteristics of the power meter.
Demand Readings
The power meter provides the following demand readings.Demand Calculation Methods
Power demand is the energy accumulated during a specified period divided by the length of the period. Current demand is calculated using arithmetical integration of the current RMS values during a time period, divided by the length of the period. How the power meter performs this calculation depends on the selected method. To be compatible with electric utility billing practices, the power meter provides block interval power/current demand calculations.
For block interval demand calculations, you select a block of time (interval) that the power meter uses for the demand calculation and the mode the meter uses to handle he interval. 2 different modes are possible:
• Fixed block - Select an interval from 1 to 60 minutes (in 1 minute increments). The
 power meter calculates and updates the demand at the end of each interval.
• Sliding block - Select an interval from 1 to 60 minutes (in 1 minute increments). For demand intervals less than 15                 minutes, the value is updated every 15 seconds. For demand intervals of 15 minutes and greater, the demand value is updated every 60 seconds. The power meter displays the demand value for the last completed interval.
Peak Demand
In nonvolatile memory, the power meter maintains a maximum operating demand value called peak demand. The peak is the highest value (absolute value) for each of these readings since the last reset.
You can reset peak demand values from the power meter display. You should reset peak demand after changes to basic power meter setup such as power system configuration.
Energy Readings
The power meter calculates and stores Per phase and total energy values for active,reactive, and apparent energy.
You can view energy values from the display. The resolution of the energy value automatically changes from kWh to MWh to GWh (kVAh to MVARh to GWh).
The energy values automatically resets to 0 when it reaches the limit of 999.9GWh,
999.9GVAh, or 999.9GVARh.

Minimum/Maximum Values
When any one-second real-time reading reaches its highest or lowest value, the power meter saves the minimum and maximum values in its nonvolatile memory.
From the power meter display, you can:
• view all min./max. values since the last reset and the reset date and time.
• reset min./max. values.
All running min./max. values are arithmetic minimum and maximum values. For example, the minimum phase A-N voltage is the lowest value in the range from 0 to 999.9GV that has occurred since last reset of the min./max. values.
The power meter provides time stamping for all minimum/maximum values.
The following table lists the minimum and maximum values stored in the power meter:
 
Minimum/Maximum Values
When any one-second real-time reading reaches its highest or lowest value, the power meter saves the minimum and maximum values in its nonvolatile memory.
From the power meter display, you can:
• view all min./max. values since the last reset and the reset date and time.
• reset min./max. values.
All running min./max. values are arithmetic minimum and maximum values. For example, the minimum phase A-N voltage is the lowest value in the range from 0 to 999.9GV that has occurred since last reset of the min./max. values.
The power meter provides time stamping for all minimum/maximum values.
The following table lists the minimum and maximum values stored in the power meter: