Hardware manual PCD7.LRxx-PG5 room controller │ Document 27-653; version ENG07 │ 2019-03-21
Saia-Burgess Controls AG
S-Bus/ModBus room operating device on RS-485 interface
Room operating devices
7-13
7
7.3
PCD7.D1000 S-Bus/Modbus room operating device
on RS-485 interface
Wall unit for room temperature measurement, setpoint
offset control and quick cool operation. The design
matches the PEHA Dialog Aluminium wall switch range.
The wall unit is connected to a Saia PCD by a RJ9
cable including 24 V DC power supply and bus
communication. It is controlled via RS-485 serial
communication protocol S-Bus or Modbus.
Data points can be read and written from the controller
via S-Bus and Modbus registers.
For more detailed information, please refer to the data
Features
●
Design according PEHA Dialog Aluminium
● Room temperature sensor 0…40°C
● Setpoint offset c/- 3 K in increments of 0.5 K
● Seven LEDs for signalling the setpoint offset
●
Two plug-in RJ9 connectors for daisy chain connection of up to six wall units
●
S-Bus/Modbus protocol for data exchange with Saia PCD systems
With Modbus, the standard Modbus library can be used and FBoxes can be sent
and received
Recommended max. distance between room controllers and room operating
devices type PCD7.LR-TR40x / PCD7.LR-TR42x
Single twisted pair,
no shielding,
stranded or wire
A)
Standard untwisted thermostatic cable,
with or without shielding,
stranded or wire
B), C)
0.33…0.82 mm
2
(18…22 AWG)
0.20 mm
2.
(24 AWG)
0.20…0.82 mm
2
(18…24 AWG)
150 m
(500 feet)
120 m
(400 feet)
30 m
(100 feet)
A) As a general rule of thumb, a twisted pair (just two wires per cable), thicker diameter and unshielded cable achieves the best results for longer
lengths.
B) The 30 m distance is conservative for standard thermostat cables, but this limit only serves to reduce the effects of sources of interference (includ
-
ing but not limited to frequency converters, electronic ballasts, etc.) Shielded cables are only recommended where necessary to reduce the effect of
electrical interference.
C) These distances also apply to twisted wire pairs.
