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64
CMS-700 SYSTEM CIRCUIT MONITORING SYSTEM (CMS)
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FAQ
Number
Topic
1
Current limit mains
power factor
2
Energy value
3
Max. energy value
4
Modbus
5
Modbus TCP
6
Master / Slave
7
Master / Slave
8
Current direction
Explanation
The CMS-700 gathers mains and N phase currents L1, L2, L3 based on the secondary current of the current
transformer starting from a current of 60mA. Below 60mA, the current value is shown as 0A.
For the primary current with a 20/5 current transformer this means: 60mA * 20/5 = 60mA * 4 = 240mA (phase
current). Below a line current of 240mA, the current value is shown as 0A.
If the CMS-700 measures no mains current (= 0A), the power factor is 1.
Only the accumulated energy value can be read.
In order to obtain values for 15 minutes, the control system (master system) needs to poll data every 15
minutes and then subtract the last value (previous 15 minutes).
The max. energy value for the mains and the individual branches is 429'496 kWh each.
Modbus values can be read in blocks. The Modbus protocol recognizes the "Read Holding Register" (03h)
function code. This means that the start address (start register) and the number of registers to be issued are
defined (see p. 40 - Read ongoing measurement values of sensor 5-16).
The RJ45 LAN connection of the device is compatible with Modbus TCP.
The CMS-700 does not have a master function. It operates as a slave and can be addressed accordingly in the
Web UI configuration.
Each CMS-700 needs its own IP address on the network and must be accessed using this IP address.
There is no current direction detection for AC. For DC measurement, the current direction is detected via
Modbus reading.
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