IOMod 4Cs4Vs is a compact-sized stand-alone power meter used for measuring analog AC input signals from low power current and voltage sensors. It measures three phases of AC voltages and currents with additional input for neutral/residual voltage and current. Measured and calculated values transmitted to the host system via industry standard IEC 60870-5-103 and Modbus RTU communication protocols.
IOMOD 4Cs4Vs User Manual
IOMod 4Cs4Vs is a compact-sized stand-alone power meter for measuring analog AC input signals from low-power current and voltage sensors. It measures three phases of AC voltages and currents with additional inputs for neutral/residual voltage and current. The measured and calculated values are transmitted to the host system via communication protocol IEC 60870-5-103 or Modbus RTU.
- 4 AC current sensor inputs according to IEC 60044-8 (nominal value 225mV)
- 4 AC voltage sensor inputs according to IEC 60044-7 (nominal value 3.25/ √3 V)
- Communication protocols : IEC 60870-5-103 or Modbus RTU
- 32 samples per cycle
- FFT-based calculation with harmonic information
- RS485 interface with a switchable terminating resistor
- Status and data transmission (Rx and Tx) indication.
- Configurable over USB
- Drag-and-Drop firmware upgrade over USB
- A small-sized case with a removable front panel
- DIN rail mount
- Operating temperature: from -30 to +70°C
- Power Requirements: 12-24 VDC
Common configuration information
- Nominal system frequency. In order to get correct three-phase system measurements, a user must select nominal system frequency – either 50Hz or 60Hz.
- Process parameters. There user can set rated primary current and voltage values which are used for calculating measured data in primary values. Those values are available only via float registers in the Modbus RTU protocol.
- Configuration of sensors. The power meter is designed to work with standard low-power current and voltage sensors with a nominal output value of 225mV for the current sensor and 3.25√3 V (1.876V) for the voltage sensor. If current sensors have some deviation from the nominal value, a user can define the exact sensor voltage. The new value will be set the same for all current sensors inputs. Each voltage sensor input has a separate correction parameter called the magnitude factor. This factor is used to multiply measured voltage. For example, if a sensor has a 5% lower output voltage, the user can set the magnitude to 1050. The actual factor will be 1.05 and the measured value will be multiplied by this factor. This factor can be used in cases when several measuring devices are connected to the same sensor in parallel. In this case, the parallel connection will reduce the internal resistance of the sensor and consequently output voltage. The magnitude factor can be used to compensate for this deviation.
- Communication protocol. Selection of IEC 60870-5-103 or Modbus RTU communication protocol.
Fig. 4.1. IOMOD 4CS4VS internal structure and connection diagram
|1.||Dimension||101 x 119 x 17.5 mm|
|4.||Working temperature||-30 | +70|
|5.||Recommended operating conditions||5 – 60°C and 20 – 80%RH;|
USB – configuration terminal via com port
|7.||Firmware upgrade||USB – mass storage device|
Input resistance: ~1 MOhm
Input capacitance: ~170pF
|9.||Power Supply||9V to 33V|
|10.||Current consumption||40mA @ 12VDC, 20mA @ 24VDC|
IOMod 4Cs4Vs has an integrated 120Ω termination resistor, which can be enabled or disabled via the configuration terminal. It is recommended to use termination at each end of the RS485 cable. See the typical connection diagram in Fig. 6.1.
Fig. 6.1. Typical IOMod connection diagram
IOMod 4Cs4Vs has a 1/8 Unit load receiver which allows having up to 255 units on a single line (compared to standard 32 units). To reduce reflections keep the stubs (cable distance from the main RS485 bus line) as short as possible.
Configuration over USB
The device requires USB drivers to work as a Virtual COM port. The first-time connection between the device and the computer could result in a “Device driver software was not successfully installed” error (as in Fig. 7.1).
Fig. 7.1. Unsuccessful device software installation error
A user then should manually install drivers by selecting a downloaded driver folder:
- Go to Control Panel -> Device Manager;
- Select a failing device;
- Press “Update driver software”; the screen as in Fig. 7.2. should appear: