Emerson FloBoss 107 Instruction Manual page 50

FloBoss 107 Instruction Manual
Power
Requirements
Terminal Blocks
PWR (IN + / IN –)
LOOP and GND
3-2
to all local and National Electrical Code (NEC) requirements for power
installations.
A dc voltage source is the typical source of primary power for FB107
installations. The FB107 accepts input voltages from 8.0 volts to 30
volts either at the AUX PWR IN connection on the base unit or at the
PWR (IN+ / IN−) terminals on the CPU. The AUX PWR IN terminal
block accepts wires from size 12 to 22 AWG.
Note: For a fully loaded eight-slot FB107, the maximum power for a dc
voltage source should not exceed 22 watts.
The power consumption of an FB107 and the attached expansion racks
determines the current requirements for the external power supply.
The CPU module's power input has a removable terminal block for
wiring and servicing. The terminal blocks can accept size 16 to 24
AWG (American Wire Gauge).
Note: Isolation occurs between the CPU and the field logic.
Using ROCLINK 800, you can configure the I/O on the CPU module to
set the loop output power to 10 volts dc or 24 volts dc using ROCLINK
800. The I/O module only supports 24 volts dc loop output power.
Note: The CPU I/O assembly uses the CPU's loop power output and
ground connections.
The intent of the loop output power is to power devices that require 24
volts dc to ground, allowing the external device to send the FB107 a 4 to
20 mA signal based on pressure, temperature, level, and such.
The 10-volt loop output power is intended for low power transmitters.
The loop current is designed to deliver 80 mA to power two field
devices that connect back to the two analog inputs.
Note: If the input voltage is greater than the 10-volt loop, then the loop
voltage equals the input voltage. For example, if the PWR IN is
14 volts dc and you select a 10-volt loop, the loop output equals
14 volts dc.
You can use current analog inputs of 4 to 20 mA when the 250-ohm
resistor is selected in the AI configuration using ROCLINK 800.
Table 3-1. Input Terminal Block Connections
Accepts up to 28 Volts dc nominal from an AC/DC converter
or other 28 volts dc supply.
Supplies 10 Volts dc or 24 Volts dc source voltage to
external field devices. Current limit protected.
Power Connections
Definition Volts DC
8 to 30 Volts dc
10 Volts dc or 24 Volts
dc
Issued Feb-07