Simex SLIK-638, Руководство пользователя

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User manual - COUNTER SLIK-638
5 - the value of the “ mbAccE ” parameter is also connected to write to this register, so it is possible to block a writes,
but impossible to unblock writes via RS-485 interface, The unblocking of the writes is possible from menu level only.
6 - n umbers written to holding registers of relays thresholds are interrelated with each other auto-correction.
For example. Preset to reg. 31h (threshold lower word) of value, which together with content of register 30h
(threshold higher word) gets value from behind of allowable range, will fails. Over more preset to reg 30h of value
which together with content of register 31h gets value from behind of allowable range, will modify the content of
register 31h, in that way to it's value together with register 30h be located in allowable range. If appropriate
modification is impossible, write fails.
It is recommended to write threshold values in presented manner: first preset of
threshold higher word, and next threshold lower word. Similarly storing of thresholds registers of another relays is
being realised with each other correction.
9.2. TRANSMISSION ERRORS DESCRIPTION
If an error occurs while write or read of single register, then the device sends an error
code according to Modbus RTU specifications.
Error codes:
01h
- illegal function (only functions 03h, 06h and 10h are available),
02h - illegal register address
03h - illegal data value
08h - no write permission ( see: “ mbAccE ” parameter)
9.3. EXAMPLES OF QUERY/ANSWER FRAMES
Examples apply for device with address 1. All values are represent hexadecimal.
Field description:
ADDR
Device address on Modbus network
FUNC Function code
REG H,L Starting address (address of first register to read/write, Hi and Lo byte)
COUNT H,L
No. of registers to read/write (Hi and Lo byte)
BYTE C
Data byte count in answer frame
DATA H,L Data byte (Hi and Lo byte)
CRC L,H CRC error check (Hi and Lo byte)
1. Read of device ID code
ADDR FUNC REG H,L COUNT H,L CRC L,H
01 03 00 21 00 01 D4 00
The answer:
ADDR FUNC BYTE C DATA H,L CRC L,H
01 03 02 20 C6 98 22
DATA - identification code (20C6h)
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