Basic Documentation

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Siemens Actuators SAX.., SAY.., SAV.., SAL.. for valves CE1P4040en
Smart Infrastructure Functions and control 2020-01-30
Communication
Communications protocol Modbus RTU RS-485, not galvanically separated
Number of nodes Max. 32
Address range 1...248 / 255
Factory settings: 255
Transmission formats 1-8-E-1 / 1-8-O-1 / 1-8-N-1 / 1-8-N-2
Factory settings: 1-8-E-1
Baud rates (kBaud) Auto / 9,6 / 19,2 / 38,4 / 57,6 / 76,8 / 115,2
Factory settings: Auto
Bus termination 120 Ω electronically switchable
Factory settings: Off
Function codes
03 (0x03) Read Holding Registers
04 (0x04) Read Input Registers
06 (0x06) Write Single Register
16 (0x10)
Write Multiple Registers (Limitation: Max. 120 registers on one write access)
4.13.6 Function description
The setpoint of the controller for the position to move to, 0…100% stroke/angle of
rotation, resolution 0.01, i.e. 0% = 0 and 100% = 10000.
The actual value reported by the device, with the same resolution.
The actuator can be operated in override control for commissioning / maintenance
purposes or system-wide functions (e.g. night-cooling).
· Manual override: When the manual adjuster is used, a mechanical jam will
be detected if a mismatch between setpoint and actual position persists for
more than 10s.
· Remote override: The actuator enters this state when an override
command is sent over the bus.
· Available commands:
- Extend / Retract
- Stop (with braking distance compensation)
Restarting is possible by:
· Power-reset (turning operating voltage off and on) or
· “Reinitialize” command.
à Device re-initializes and sets all process values except actual value (= 50%)
and setpoint (= startup setpoint) to defaults.
When triggered, the self test drives the actuator to the detected limits and sets the
flags in register 769 according to the result (bit 09 = 1à”failed” or bit 10 = 1 à
“passed”).
The self test is not passed when the limits were not reached from the lower end
(results in jam). If the Min/Max limits can be exceeded, the self test is not evaluated
as failed.
· The self test can only be performed if bit 4 = 0 in register 769 “Status”,
meaning there is concurrently no clogging or manual operation.
Communication
properties
Supported function
codes
Register 1 / 3
“Setpoint / actual value”
Register 2
“Override control”
Register 256
“Restarting the device”
Register 256
“Self test”
Notes