Watlow PPC-2000 - Manual (Page 106)

Chapter 2: Hardware Installation PPC-2000 User’s Guide
82 Watlow Anafaze Doc.# 30002-00 Rev 2.3
The host computer uses one twisted pair to send messages to
any PPC on the network. All the PPCs receive all the messages.
The one PPC addressed by a particular message uses the other
twisted pair to respond. This twisted pair is shared by the
transmitters of all the PPCs on the network. Only one PPC
transmits at a time.
Therefore, one twisted pair connects the transmitter terminals
at the host computer or converter to the receivers on each of the
controllers. The second twisted pair connects the computer or
converter’s receiver to the transmitters on all the PPCs on the
network. Figure 2.71 illustrates this.
Network wiring should approximate a daisy chain as closely as
possible. Keep the distance from the point at which the wires
are split to the PPC as short as possible. Long spurs can cause
destructive interference of the signals.
Figure 2.71 RS-485 Wiring
485 Terminal Block
The 485 terminal block accepts an RJ12 cable connector and
converts each line on the cable to a screw terminal. Use the 485
terminal block to wire multiple PPC-2000 controllers together
on the same 485 network. Pins on the terminal block are
designated 1 to 6. The function and number of each pin
corresponds to the function and pin numbers of the 485 ports
on the PPC-2010 module.
PPC 1 PPC N
TXA/TDA/TX-
DC Common
Yellow (5)
Black (2)
Green (4)
Red (3)
White/Blue (1)
RA-
RB+
TA-
TB+
Signal
Common
Not Used
External
Termination
Resistor RA-
RB+
TA-
TB+
Signal
Common
Not Used
TXB/TDB/TX+
RXA/RDA/RX-
RXB/RDB/RX+
Color (RJ Pin) Converter or Host
Yellow (5)
Black (2)
Green (4)
Red (3)
White/Blue (1)
Color (RJ Pin)