Quencharc wiring example, Standard bus eia-485 communications, Modbus rtu or standard bus eia-485 communications – Watlow EZ-ZONE RM Limit Module Rev C User Manual
Page 28
Watlow EZ-ZONE
®
RML Module
•
25
•
Chapter 2 Install and Wire
Warning:
ç
Use National Electric (NEC) or other
country-specific standard wiring and
safety practices when wiring and
connecting this controller to a power
source and to electrical sensors or pe-
ripheral devices. Failure to do so may
result in damage to equipment and
property, and/or injury or loss of life.
Note:
Maximum wire size termination and
torque rating:
• 0.0507 to 3.30 mm2 (30 to 12 AWG)
single-wire termination or two 1.31
mm2 (16 AWG)
• 0.8 Nm (7.0 in-lb.) torque
Note:
Adjacent terminals may be labeled
differently, depending on the model
number.
Note:
To prevent damage to the controller,
do not connect wires to unused ter-
minals.
Note:
Maintain electrical isolation between
digital input-outputs, switched dc/open
collector outputs and process outputs
to prevent ground loops.
Quencharc Wiring Example
In this example the Quencharc circuit
(Watlow part# 0804-0147-0000) is used to
protect RML internal circuitry from the
counter electromagnetic force from the in-
ductive user load when deenergized. It is
recommended that this or an equivalent
Quencharc be used when connecting induc-
tive loads to RML outputs.
Quencharc
User Load
L_
K_
N
Standard Bus EIA-485 Communications
T-/R-
common
Slot C
T+/R+
98 99
CF CD CE
CZ CX CY
• Wire T-/R- to the A terminal of
the EIA-485 port.
• Wire T+/R+ to the B terminal
of the EIA-485 port.
• Wire common to the common
terminal of the EIA-485 port.
• Do not route network wires
with power wires. Connect net-
work wires in daisy-chain fash-
ion when connecting multiple
devices in a network.
• A 120 Ω termination resistor
may be required across T+/R+
and T-/R-, placed on the last
controller on the network.
• Do not connect more than 16
EZ-ZONE PM controllers on a
network.
• maximum network length:
1,200 meters (4,000 feet)
• 1/8th unit load on EIA-485 bus
RMLx-xxxx-x(A)xx
* All models include Standard Bus
communications
Note:
Do not leave a USB to EIA-485 converter connected to Standard Bus with-
out power (i.e., disconnecting the USB end from the computer while leaving
the converter connected on Standard Bus). Disturbance on the Standard
Bus may occur.
Modbus RTU or Standard Bus EIA-485 Communications
T-/R-
common
Slot C
T+/R+
98 99
CC CA CB
CZ CX CY
• Wire T-/R- to the A terminal of
the EIA-485 port.
• Wire T+/R+ to the B terminal
of the EIA-485 port.
• Wire common to the common
terminal of the EIA-485 port.
• Do not route network wires
with power wires. Connect net-
work wires in daisy-chain fash-
ion when connecting multiple
devices in a network.
• A termination resistor may be
required. Place a 120 Ω resistor
across T+/R+ and T-/R- of last
controller on network.
• Only one protocol per port is
available at a time: either Mod-
bus RTU or Standard Bus.
• Do not connect more than 16
EZ-ZONE controllers on a
Standard Bus network.
• Maximum number of EZ-ZONE
controllers on a Modbus net-
work is 247.
• maximum network length:
1,200 meters (4,000 feet)
• 1/8th unit load on EIA-485 bus
RMLx-xxxx-x(1)xx
Note:
Do not leave a USB to EIA-485 converter connected to Standard Bus with-
out power (i.e., disconnecting the USB end from the computer while leaving
the converter connected on Standard Bus). Disturbance on the Standard
Bus may occur.
Modbus-IDA
Terminal
EIA/TIA-485
Name
Watlow Terminal
Label
Function
DO
A
CA or CD
T-/R-
D1
B
CB or CE
T+/R+
common
common
CC or CF
common