144 • HRVS-DN Communication (ModBus Protocol)
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Note: For Force Single Coil Function, Force Data of $0000 forces "0" = OFF. Force data of $FF00 forces "1"
= ON. The "Query" frame is sent by the host:
byte 1: Serial Link No. ($01)
byte 2: Function ($05)
byte 3: Coil Address High ($00)
byte 4: Coils address Low ($03) Start/Stop relay
byte 5: Force Data High ($FF) (force ON)
byte 6: Force Data Low ($00)
byte 7: CRC_Low ($XX)
byte 8: CRC_High ($XX)
The normal (if no exception) response:
byte 1: Serial Link No. ($01)
byte 2: Function ($05)
byte 3: Coil Address High ($00)
byte 4: Coils address Low ($03)
byte 5: Force Data High ($FF)
byte 6: Force Data Low ($00)
byte 7: CRC_Low ($XX)
byte 8: CRC_High ($XX)
Notes:
1. Hardwired Stop and Soft Stop inputs, overrides the communication. To enable motor starting through
communication, terminal 4 (Stop) must be connected to the control voltage. Connect Terminals 5 & 6
to control voltage through the HRVS-DN Start/Stop optional relay output contact.
2. Start/Stop coil and Dual Adj coil should be of maintained type, like a toggle switch.
3. Reset coil should be of momentary type, like a momentary reset pushbutton. It is Rejected, if given
together with Start command.
4. Before reseting, be sure to turn off start/stop relay coil first.
5. It is the host responsibility, to immediately write a Stop command when detecting that the Trip bit is set
in the Logic_Status parameter (parameter # 1 in the Actual data). This is to prevent unwanted start
command upon resetting the fault.