Hitachi WJ200-001L, Instruction Manual, Page: 238 / 680

4

31
Three-wire Interface Operation
The 3-wire interface is an industry standard motor control interface. This function uses
two inputs for momentary contact start/stop control, and a third for selecting forward
or reverse direction. To implement the 3-wire interface, assign

[STA] (Start),

[STP] (Stop), and

[F/R] (Forward/Reverse) to three of the intelligent input terminals.
Use a momentary contact for Start and Stop. Use a selector switch, such as SPST for
the Forward/Reverse input. Be sure to set the operation command selection

=

for
input terminal control of motor.
If you have a motor control interface that needs logic-level control (rather than
momentary pulse control), use the [FW] and [RV] inputs instead.
Option
Code
Terminal
Symbol
Function Name State Description

STA Start Motor ON Start motor rotation on momentary contact (uses
acceleration profile)
OFF No change to motor operation

STP Stop Motor ON No change to motor operation
OFF Stop motor rotation on momentary contact (use
deceleration profile)

F/R Forward/Reverse ON Select reverse direction of rotation
OFF Select forward direction of rotation
Valid for inputs:

~

Example (default input configuration shown):
See I/O specs in chapter 4
.
Required settings

=

Notes:

The STP logic is inverted. Normally the switch will
be closed, so you open the switch to stop. In this
way, a broken wire causes the motor to stop
automatically (safe design).

When you configure the inverter for 3-wire
interface control, the dedicated [FW] terminal is
automatically disabled. The [RV] intelligent
terminal assignment is also disabled.
The diagram below shows the use of 3-wire control. STA (Start Motor) is an
edge-sensitive input; an OFF-to-ON transition gives the Start command. The control of
direction is level-sensitive, and the direction may be changed at any time. STP (Stop
Motor) is also a level-sensitive input.
[STP] terminal
1
0
t
[F/R] terminal
1
0
Motor revolution
speed
[STA] terminal
1
0
F/R STP STA
7 6 5 4 3 2 1 L P24 PLC