Sullair SUPERVISOR CONTROLLER Series Protocol Manual

Section 1
SUPERVISOR PROTOCOL
6
ANALOG SHUTDOWN TABLE
RS-485 SERIAL CHANNEL
The RS-485 is a party line type channel, ie. any device on the channel may transmit or
receive on the same wires. The transmitters and receivers are differential type that use two
wires and a ground. These have very good noise immunity because the receiver measures
the voltage between two signals, and not between a signal and ground (as RS-232 does).
If noise occurs on both lines it will be rejected by the receiver. The ground is used to keep
the receiver from floating too high above the transmitter.
A one is transmitted as 5 volts on the + line and 0 volts on the - line. A zero is 0 volts on the
+ line and 5 volts on the - line.
The transmitters are tri-state, meaning they can drive the transmission line to a one (5
volts), zero (0 volts) or be turned off (high impedance). All transmitters except one must be
in tri-state mode, otherwise the transmission will be garbled and damage to the transmitters
can occur.
1 = P1
2 = P2
3 = P3
4 = P4
5 = dP1
6 =dP2
7 = dP3
8 = T1
9 = T2
10 = T3
11 = T4
12 = T5
13 = T6
Transmitter Receiver
+
-
+
-
Up to 4000’
GND
GND
+ line
- line
Receiver
+5v
0v
+5v
0v
1
0

Sullair SUPERVISOR CONTROLLER Series Specifications

General

Brand	Sullair
Model	SUPERVISOR CONTROLLER Series
Category	Controller
Language	English