Scaime eNod3-C, Инструкция пользователя

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e Nod3- C
Digital Transmitter
e Nod3- C :
User’s instructions
NU-eNod3C-E-0911_165702-I
10/22
e Nod3- C
can communicate using several protocols:
- ModBus RTU
- SCMBus standard
format or
fast
format.
- CANopen®
 Switching from the
SCMBus
protocol to the
ModBus-RTU
protocol (and reciprocally) can be
done by software programmation.
1) send the corresponding command
2) send the ‘storage in EEPROM’ command
3)
reset (hardware or software)the device
See example describing how to switch from
ModBus-RTU
to
SCMBus
protocol in the
document
SCMBUS communication Ref 165 706
Appendix A.
 Switching from
SCMBus/ModBus-RTU
protocol to
CANopen®
protocol (and reciprocally)
can be done by setting or removing the appropriate jumper (cf. §3) then by making a
reset
3.1 ModBus RTU:
See the description of the frames and functions in the ‘
ModBus RTU
communication protocol’ Ref.
165 704 document.
3.2 SCMBus:
See the description of the frames and functions in the ‘
SCMBus
communication protocol’ Ref.
165 706 document.
The
SCMBus
protocol has got similarities with
ModBus-RTU.
It is based on the master/slave
structure however it allows to transmit measurements continuously without collision management
on the line. This operating mode is only available in
transmitter
functioning mode.
The measurements transmission frequency depends on the serial baud rate thus transmitting 100
meas/s is impossible at less than 19200 bauds. For fast measurement transmissions, use the
fast
SCMBus format
with wich 1200 meas/s can be expected at 115200 bauds.
Other methods of transmitting information without any master request :
-
transmitter mode
: measurement transmission triggered by a digital input.
- whatever the functioning mode is , physical calibration procedure :
automatic
transmission when a step in the process is complete.
3.2.1 Fast SCMBus format:
The
Fast SCMBus
format is particularly useful for measurement acquisitions at the highest
frequency, for example, in order to analyse dynamic phenomena.
This format should only be used for point-to-point operation in full-duplex.
To optimize the speed, in addition to using the
Fast SCMBus
format, it is preferable to configure
e Nod3- C
for operation with
‘no processing transmitter’
. In this configuration, filters are inactive, set-
points are not managed and there is no polynomial linearization.
3.3 CANopen®
e Nod3- C
supports
CANopen®
communication protocol and is compliant with
‘CIA® Standard
V301’
. See the description of the frames and functions in the ‘
CANopen®
communication protocol’
Ref. 165 717 document.