142 • HRVS-DN Communication (ModBus Protocol)
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allowed limit, the limit value will be stored instead the transmitted parameter value. It is the user’s
responsibility to read and check all parameter settings after presetting.
16.9
Control Register Write (4X Reference)
The HRVS-DN incorporates
one
Control register intended for controlling the HRVS-DN.
Address: The Control register is register # 753 addressed as 752 (40752).
In order to control the HRVS-DN using the Control register:
* Use Function 16 only.
* Use Address_High (page) = 2
* Use Address_Low = 240 (0F0H).
* Write to one register only.
* Use data_high (ms-byte of data) = 5AH.
* Data_low Bits resolution of the control register (ls-byte of data):
bit
function
Comment
Note
d0
Reserved.
d1
Reserved.
d2
Reserved.
d3
Start/Stop Relay
Write "1" (ON) to Start / Run. Operates relay (terminals 31-32)
Write "0" (OFF) to Stop.
Located in the Control Module
optional
Relay
Card.
d4
Dual Adjust
Write "1" (ON) to turn On.
Write "0" (OFF) to turn Off.
d5
Reserved.
d6
Reserved.
d7
Reset
Write "1" (ON) to Reset.
Notes:
1. Read function of the control register is not available. To read the HRVS-DN status, read Logic
Status (Actual parameter # 1).
2. Bytes 2..8 of the control frame must be exactly as in the following example. Otherwise, an error
message is returned.
3. 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.
4. Start/Stop and Dual Adj bits, should be of maintained type, like a toggle switch.
5. Reset bit should be of momentary type, like a momentary reset pushbutton. It is rejected, if
given together with Start command.
6. Before (or simultaneously with) resetting, be sure to turn off start/stop relay bit first.
7. It is the host responsibility, to immediately write a Stop command (writing 5A00 Hex) when
detecting that the Trip bit is set in the Logic Status parameter (parameter # 1 on the In data).
This is to prevent unwanted start command upon resetting the fault.
Example 5 - Control Register Write:
To start HRVS-DN # 11, the host computer sends the following Query frame:
byte 1: Serial Link No.
($0B)
byte 2: Function
($10)
Bytes 2..8 must be as in this example!!!
byte 3: Starting Address High
($02)
byte 4: Starting Address Low
($F0)
byte 5: No. of Registers High
($00)
byte 6: No. of Registers Low
($01)
byte 7: Byte Count
($02)
byte 8: Data High
($5A)
byte 9: Data Low
($08)
Bit 3 is set, to start.
