Hitachi L200 Series, Instruction Manual

Page: 137 / 280

L200 Inverter
Oper
ations
and Monitor
ing
4–9
Using Intelligent Input Terminals
Terminals [1], [2], [3], [4], and [5] are identical, programmable inputs for general use.
The input circuits can use the inverter’s internal (isolated) +24V field supply or an
external power supply. This section describes input circuits operation and how to
connect them properly to switches or transistor outputs on field devices.
The L200 inverter features selectable sinking or sourcing inputs. These terms refer to the
connection to the external switching device—it either sinks current (from the input to
GND) or sources current (from a power source) into the input. Note that the sink/source
naming convention may be different in your particular country or industry. In any case,
the just follow the wiring diagrams in this section for your application.
The inverter has a DIP switch for config-
uring the choice of sinking or sourcing
inputs. To access it, you must remove the
front cover of the inverter housing. In the
figure to the right, the SR/SK switch
(“source/sink switch”) is shown as
located on the circuit board, at the right
end of the logic signal connector.
DO NOT confuse it with the two, larger
configuration switches nearby. The circuit
board has the SR and SK markings above
and below the switch as shown.
CAUTION: Be sure to turn OFF power to the inverter before changing the SR/SK
switch position. Otherwise, damage to the inverter circuitry may occur.
[PCS] Terminal Wiring - The [PCS]
terminal (Programmable Control System
terminal) is named to include various
devices that can connect to the inverter’s
logic inputs. In the figure to the right,
note the [PCS] terminal and the nearby
diodes and DPDT switch. The upper part
of the SR/SK switch selects between
connecting the inverter’s +24V internal
supply to [PCS] or allowing an external
supply power to connect. The lower part
of the SR/SK switch selects between
connecting the input circuit common node
to either Logic GND or the +24V supply.
The wiring diagrams on the following
pages show the four combinations of
using sourcing or sinking inputs, and
using the internal or an external DC
supply.
SR
SK
SR
SK
Legend:
Source
(default)
SR
SK
Sink
Logic inputs
1 2 3 4 5 L PCS
L200
L
24V
+
–
SK
SR
SK
SR
PCS
Input
circuits
1
5
Logic GND
Input common