CIRCUTOR, SA reserves the right to modify features or the product manual without prior notifi cation. DISCLAIMER CIRCUTOR, SA reserves the right to make modifi cations to the device or the unit specifi ca- tions set out in this instruction manual without prior notice.
CEM M-RS485 REVISION LOG Table 1: Revision log� Date Revision Description 07/14 M014B01-03-14A Initial Version Changes in the following sections: 01/15 M014B01-03-15A 4.4.4. Instruction Manual...
If any problem is noticed upon reception, immediately contact the transport company and/or CIRCUTOR's after-sales service. 2�- PRODUCT DESCRIPTION The CEM M-RS485 optical-electric interface converts the optical service port of any unit of the CEM range into an RS-485 port with MODBUS protocol. The unit features: - 3 indicator LEDs: POWER, LINK and COMS.
The CEM M-RS485 unit must be installed by authorised and qualified staff. The power supply plug must be disconnected before handling, altering the connections or replacing the unit.
Before connecting the unit, you must couple it to a CEM energy meter as shown in Figure 1 Figure 2 Figure 1: Coupling the CEM M-RS485 to a CEM energy meter� Figure 2: Coupled CEM M-RS485 and CEM� Terminals, opening covers or removing elements can expose parts that are hazardous to the touch while the unit is powered.
The unit's operating temperature is between -25ºC and +70ºC; always use con- nection cables that can withstand these temperatures. 3.3.- UNIT TERMINALS Table 2:List of CEM M-RS485 terminals� Unit terminals 1: Auxiliary power supply. 3: A(+), RS-485 2: Auxiliary power supply.
The RS-485 cable must be made up of a twisted pair cable with a braided shield with a maximum distance of 1,200 metres between the CEM M-RS485 and the master unit. A maximum of 32 units can be connected to this bus.
CEM M-RS485 4�- OPERATION The CEM M-RS485 is designed to be used as a RS-485 electrical port for any device in the CEM family, using the mechanical coupling next to the optical port. 4.1.- OPERATING PRINCIPLE The CEM M-RS485 is an optional accessory for electrical energy meters from the CEM range that are mounted on DIN rails.
Within the MODBUS protocol the CEM M-RS485 uses the RTU (Remote Terminal Unit) mode. In RTU mode, message starts and ends are detected with silences of at least 3.5 characters, and the 16-bit CRC error-detection method is used.
The number of requested logs must be the same as the size of the variable requested. It is possible to read several consecutive addresses, if the request meets the correct format. 4�4�3�- WRITE COMMANDS The CEM M-RS485 supports integer type write functions: 0x01. The unit's Modbus variables are specified in Table 4 Example: Changing the Modbus address of peripheral 01 to the address 0x000A.
32 bits resolution Note: Some MODBUS variables may not be available depending on the CEM energy meter coupled to the CEM M-RS485. See “4.4.4.7.- Available addresses by unit” 4�4�4�2�- Energy The Read function is implemented for these variables. Table 5: Modbus variables: Energy...
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( 1 decimal place) Note: Some MODBUS variables may not be available depending on the CEM energy meter coupled to the CEM M-RS485. See “4.4.4.7.- Available addresses by unit” 4�4�4�4�- Instantaneous values The Read function is implemented for these variables.
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16 bits Note: Some MODBUS variables may not be available depending on the CEM energy meter coupled to the CEM M-RS485. See “4.4.4.7.- Available addresses by unit” Energy meter model description table, Table 9� Table 9: Energy meter model description table�...
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CEM M-RS485 bytes en formato Opciones C10 C20 ASCII 50Hz Frequency 60 Hz Automatic (50/60Hz) Without communications Communications Side optical service port Without inputs/outputs ...
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CEM M-RS485 Dirección Descripción 0x00C0 Cost of the partial consumption 0x00C2 KgCO atmospheric emissions of the partial consumption 0x00C4 Partial operating time 0x00C6 Total operating time 0x0732 Phase 1 voltage ...
CEM M-RS485 5�- TECHNICAL FEATURES Power supply Rated voltage 230 V~ ± 20% Maximum power consumption 4 VA Frequency 50/60 Hz with no differentiation Insulation AC voltage 4kV RMS 50Hz during 1 minute Overimpulse 1�2/50ms 0Ω source impedance 6 kV at 60º and 240º, with positive and negative polarization...
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CEM M-RS485 Figure 6: CEM M RS-485 dimensions� Instruction Manual...
• CIRCUTOR accepts no liability due to the possible damage to the unit or other parts of the installation, nor will it cover any possible sanctions derived from a pos- sible failure, improper installation or “improper usage”...
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