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LevelMaster 7100 User manual 2105835 Rev AA | 24
Selecting wire type
The power and communication terminals connectors support 12 AWG to 22 AWG. Wire gauge selection should be based on the
voltage and current requirements of the circuitry as well as the expected length of the wires. The gauge differs for each
application:
Wiring for communication must conform to RS-485 specifications and limits (Table 5, Wiring limits on the RS-485 bus ).
Wiring for power is based on how the LevelMaster is powered: using an external power supply or the output power from the
controller RS-485 (COM) port.
Wiring through a barrier must conform to the hazardous location specifications and limitations (Table 6, Wiring limitations
when using barrier boards , on page 35).
Follow local electrical codes when selecting the appropriate wire gauge and type based on the load current, voltage, signal type,
wire length, and location.
IMPORTANT NOTE: The terminal connectors on the LevelMaster board are 2 and 4-position Phoenix Contact
®
removable connector type with screw termination. The connectors can handle more than one wire in each position
when connecting multiple LevelMasters, depending on the gauge and type of wire chosen. Review the Phoenix
Contact
®
terminal connection specifications for acceptable wire gauge and type when connecting multiple wires to
a single contact point. There are limits defined for the wire conductor's cross section area based on whether
stranded or solid wires are used.
Wiring the first LevelMaster
Wiring requires wire termination at both the LevelMaster and the host controller or additional units. The procedures in this
section describe the wiring at the first LevelMaster end. The first LevelMaster on an RS-485 bus is the unit that connects to the
host controller directly or through a barrier. All communication and power to additional units depend on this connection.
Wiring is completed with termination at the host controller and additional units. After wiring the LevelMaster end and adding
additional units (if required), wire the host controller as described in section 4.5,
Wiring the host controller .
IMPORTANT NOTE: It is assumed that the wires for both communication and power will be run through the
conduits and that the wire length conforms to the specified limits. Wire length limits vary based on the installation
scenario. Wire ends must be run through the entry holes until they are visible inside the enclosure.
Wiring for communication
The LevelMaster supports serial communication on the RS-485 port (4-position terminal connector, J11 in Figure 21). Two pin
pairs are available for two RS-485 connections on this port:
Outer (T+, T-) pair, first and fourth pin on J11
Inner (T+, T-) pair, second and third pin on J11
D9
J12
1
3
J11
POWER
EARTH
T- T- T+ T+
- +
B
u
s
(-
)
B
u
s(
+
)
To host controller RS -485 port:
1) Direct connection or
2) Through barrier
Figure 21: Wiring for communication with host controller (first or only LevelMaster)