User guide

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 mm
2
(30 to 12 AWG)
single-wire termination or two 1.31
mm
2
(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.
Warning: ç
Explosion Hazard – Substitution of
component may impair suitability for
CLASS I, DIVISION 2.
Warning: ç
Explosion Hazard - Do not disconnect
while the circuit is live or unless the
area is known to be free of ignitable
concentrations of flammable sub-
stances.
Watlow EZ-ZONE
®
RMH Module • 30 • Chapter 2 Install and Wire
Quencharc Wiring Example
• In this example the Quencharc
circuit (Watlow part# 0804-0147-
0000) is used to protect internal
circuitry from the counter elec-
tromagnetic force from the induc-
tive user load when deenergized.
It is recommended that this or
an equivalent Quencharc be used
when connecting inductive loads
to outputs.
Quencharc
User Load
N
L
_
K
_
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 termi-
nal of the EIA-485 port.
• Wire T+/R+ to the B termi-
nal of the EIA-485 port.
• Wire common to the com-
mon terminal of the EIA-
485 port.
• Do not route network
wires with power wires.
Connect network wires in
daisy-chain fashion when
connecting multiple de-
vices in a network.
• A 120 Ω termination resis-
tor 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 RM control-
lers on a network.
• maximum network length:
1,200 meters (4,000 feet)
• 1/8th unit load on EIA-485
bus
RMHx-xxxx-x(A)xx
* All models include Standard
Bus communications
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 termi-
nal of the EIA-485 port.
• Wire T+/R+ to the B termi-
nal of the EIA-485 port.
• Wire common to the com-
mon terminal of the EIA-
485 port.
• Do not route network wires
with power wires. Connect
network wires in daisy-
chain fashion when con-
necting 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: ei-
ther Modbus RTU or Stan-
dard Bus.
• Do not connect more than
16 EZ-ZONE controllers on
a Standard Bus network.
• Maximum number of EZ-
ZONE controllers on a
Modbus network is 247.
• maximum network length:
1,200 meters (4,000 feet)
• 1/8th unit load on EIA-485
bus
RMHx-xxxx-x(1)xx
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
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.