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IRDH275BM-7_D00123_07_M_XXEN / 08/2020
Serial interfaces
Faults may be caused when:
• addresses are assigned twice
• a second master exists on the BMS bus
• interference signals occur on the bus lines
• a defective device is connected to the bus
• terminating resistors are not activated
5.3.2 BMS Slave
All IRDH275B are factory set to slave mode (address 3). In a BMS network, one address must be selected
from the address range 2…30 for each slave. There may be no gaps of more than five subsequent ad-
dresses, so that all slaves can be scanned by the Master. For IRDH275B a BMS address can be selected
from the address range 1…30. When assigning the addresses, also other devices such as the EDS47x-12
must be considered. The correct reception of BMS data is indicated by a flashing point on the display
on the right of the measuring pulse indication.
flashing
BMS data received
no flashing
Possible causes of faults:
• no Master available in the network
• more than one Master available in the network
• RS-485 interface (terminal A/B) not connected or
reversed
The following table gives an overview about essential alarm messages and the assignment of the mes-
sages indicated on the display or operator panels, e.g. PRC1470.
Message
Channel
Meaning
Insulation fault
1
Insulation resistance < setting Alarm 1
Insulation fault
2
Insulation resistance < setting Alarm 2
Connection PE
4
Connection error
/KE against PE
conductor
Device error
5
Internal device error
The BMS function is completely available in the standby mode (Stand-by: F1/F2).
*** I T-SY STEM***
