Dears

I see that in one of the last BOS version in the ModBus device has been introduced two new configuration settings: Read Function Type and Write Function Type.

I want to understand more how those 2 setting work: which address are written or read  at once instead separately (if I select write or read multi)? This is not clear to me… If we suppose to get only 1 modbus device connected with slave address 1 and it contains many address for eg 10, 11, 13, 20, 21, 25 and 110 (all are coils).  Is the Bos software going to write or read once all the address from 10 to 110? From the time point of view instead? If the read interval (in the BOS  Modbus confi g page) is 100 ms, does  it mean that Bos software will read or write all  the previous address data (10, 11, …, 110) in 100 ms (instead taking 100 ms each as was before)?

Regards

Marco

Hi,

Does any one can help how to configure modbus device in order to read meeters (e.g. L1 Voltage)?

I can reed some value but something is wrong with coding.

Here you have information from the manual (mull manual: http://eastrongroupco.hk02.057321.com/data/uploads/Eastron_SDM530-Modbus_protocol_V1_1.pdf)

The format for each byte in RTU mode is:

Coding System: Data Format:

Error Check Field: Framing:

8-bit per byte 4 bytes (2 registers) per parameter.

Floating point format ( to IEEE 754) Most significant register first (Default). The default may be changed if required -See Holding Register "Register Order" parameter. 2 byte Cyclical Redundancy Check (CRC) 1 start bit 8 data bits, least significant bit sent first 1 bit for even/odd parity (or no parity) 1 stop bit if parity is used; 1 or 2 bits if no parity

Data Coding All data values in the SDM530-Modbus smart meter are transferred as 32 bit IEEE754 floating point numbers, (input and output) therefore each SDM530-Modbus meter value is transferred using two Modbus Protocol registers. All register read requests and data write requests must specify an even number of registers. Attempts to read/write an odd number of registers prompt

the SDM530-Modbus smart meter to return a Modbus Protocol exception message. However, for compatibility with some SCADA systems, SDM530-Modbus Smart meter will response to any single input or holding register read with an instrument type specific value.

The SDM530-Modbus can transfer a maximum of 40 values in a single transaction; therefore the maximum number of registers requestable is 80. Exceeding this limit prompts the SDM530-Modbus to generate an exception response.

Data transmission speed is selectable between 2400, 4800, 9600,

1.2 Input register

Input registers are used to indicate the present values of the measured and calculated electrical quantities. Each parameter is held in two consecutive16 bit register.The following table details the 3X register address, and the values of the address bytes within the message. A (*) in the column indicates that the parameter is valid for the particular wiring system. Any parameter with a cross(X) will return the value zero. Each parameter is held in the 3X registers. Modbus Protocol function code 04 is used to access all parameters.

Dear Support
I got a problem with the Modbus. I need to read and write BOOL value in holding register. I try some settings that is in Jigsaw but it only work as integer, and I realy like that bool style switches that you have made. So please if it is possible please add that to jigsaw or if it possible to do it now can you tell me how? My PLC can only read and write to holding register, it will be changed but for now it is what it is. Thanks.

Dear Support

I got a problem with the Modbus. I exchange variables with the PLC (Beckhoff) using Coils… I created some buttons in the Comfort click pages and I used them to turn on and off the lights. As well I have some buttons in the Comfort Click page that show the status of the lights based on the output of the light feedback (light on or off)

When I push the light button from ComfortClick (for e.g. to turn on the light) the Modbus updates the coil status and the I see the new coils status in the PLC immediately (around 100 ms) To read the coils status from Comfort Click I used the modbus function code 01 (loading the status of all coils coming from comfortclick in one array of boolevery PLC scan)

Instead when the PLC software change the status of a coil (to update the status of the light) the comfort click tool takes up to 10 seconds to update the coil status in the ComfortClick (I monitor the Modbus bool tag status time to change from 1 to 0 or vice versa directly on the comfortclick tag value page)

To write the coils for comfortclick I used the modbus function 15 writing every 2 plc scan the status of all the coils directed to the comfortclick in an array of bool

The coils that I used to turn on the light and monitor its status are different (2 different coils with different address)

Can you help me to make the update of the coils to comfort click faster? As it is now is a pain...

Regards

Marco

Hi There,

I still cannot get my modbus connection working since about 3 updates ago, does not seem to send anything out despite showing connected.

Previously there has been a problem with it constantly disconnecting and reconnecting but this is no longer happening.

I have checked my rs485 converter and it works fine with other software as does the device I'm trying to communicate with.

The log says the command has gone out, but there is no activity on the usb/rs485 converter as I would expect.

Any ideas?

Hi,

I'm using a modbus devices (light,dimmer,ect) with moxa RTUtoTCP converter, the connection is instable and every time give me the message "Error connecting to device", after few second "Device is connected" but if try to change state I get message "Error setting value .... device is not connect ..." After few second the state change anyway but the interaction is very very slow

Any suggestion please?

Thanks a lot