CSMB
(Current Sense / Modbus)
EV loadbalancing / Energymeter
The Xemex CSMB module is a CT current meter with a Modbus Interface, which measures the current consumption of the household.
The Xemex CSMB (Current Sense / Modbus) module is a CT current meter with a Modbus Interface, which measures the current consumption of the household.
Real time total current consumption is available to the charge point via a modbus RTU/RS485 interface. With this information the charge point can calculate the current capacity which is available for charging a car.
Up to 3 CT transformers can be connected to the CSMB device. These CT transformers can be installed around the power lines without disturbing the installation. The CSMB can be used for both, single phase or poly phase installations.
The current values are stored in modbus registers and are available through the RS485 modbus interface:
Use case: EV charging station
In order to charge an electrical vehicle as quickly as possible, a residential charging station needs to know how much power of the total available grid connection is in use by the household appliances and how much is available for charging. The CSMB can be used to measure the currently used power:
Specs
Environmental conditions
- Protection class: II
- Operating temperature: -25 °C - +75 °C
- Storage temperature: 40 °C - +85 °C
-
Relative humidity:
< 75 % year’s average at 21 °C
< 95 % less than 30 days/year, at 25 °C - Pollution Degree: 2
- Altitude: < 2000m
- Application area: Residential, Indoors in suitable meter cabinet
DC Power Interface
- Connector: Screw terminal connector for 0V and +12V DC
- Voltage range: 12V DC, -50%, +10%
- Max current consumption: 50 mA
- Max cable length: 100 meter
- Cable location: indoor + outdoor
- Reverse polarity protection: yes
Cable Specifications
Preferably armoured twisted pair with drain wire. Section 0,20 … 0,50 mm². Use wires of same pair to connect B and A, wires from the other pair to +12V and 0V. Example of cable type: Belden 3107A
Metering Interface
- Connector: Screw terminal connectors for max 3 Current Transformers
- Measuring principle: Current measurement by Current transformer
- Current range: 1A ... 80A (if CT ratio = 2000)
- CT ratio: 2000 (default)
- Input impedance: 20 Ohm
- Accuracy: Typically <5 % at 23 °C
- Max Cable length: 1 meter
Modbus Interface
- Connector: Screw terminal connector for A, B and Shield
- Bus termination: 120 Ohm, switchable on/off
- Protocol: Modbus RTU over RS485
- Max cable length: 100 meter
- Cable location: Indoor + outdoor
User Interface
- Power indicator: Yellow LED
- Current indicator: Green LED
- Modbus indicator: Red LED
