Wintriss SmartPAC 2, User Manual

Page: 73 / 604

SmartPAC 2 with WPC 2000 Integration User Manual 1128600
Installation 2-29
Installing the Overrun Limit Switch
The overrun limit sensor, also called the “overrun sensor,” enables WPC 2000 to monitor
operation of the resolver and to stop the press whenever the resolver fails to work properly, as
can happen when the resolver drive chain breaks or slips or when the resolver is broken. The
overrun sensor provides a signal to WPC 2000 at the same resolver angle on every stroke.
Whenever this angle changes, WPC 2000 detects that the resolver is no longer rotating at a 1:1
ratio with the crankshaft and sends an Emergency-stop command to the press, simultaneously
displaying an error code.
Planning Your Overrun Sensor Installation
The overrun sensor consists of a magnetic switch and a magnet. Select a mounting location
for both components that ensures that the magnet moves past the switch once on every stroke
and within 1/8 in. to 3/16 in. (3 mm to 5 mm) of the switch, close enough for the switch to
sense the magnet’s presence. The magnet is mounted to the crankshaft or another component
that rotates identically on every stroke. The switch is hard-mounted to the press or other
surface and remains stationary.
There must be no connection between the overrun limit sensor and the resolver to ensure that
the overrun sensor continues to operate if the resolver or its drive mechanism fails.
To obtain an adequate overrun signal at high speeds, the magnet should be mounted so that it
can be sensed by the switch for 15° to 25° of the stroke. The interval during which the magnet
is sensed, called the “dwell,” decreases as the diameter of the rotating shaft increases (see
Figure 2-15, page 2-30). Select a shaft whose diameter will allow the sensor to detect the
magnet for the required dwell. A shaft diameter of 4 in. to 6 in. (100 mm to 150 mm) is
optimum.
MOUNT OVERRUN LIMIT SWITCH SO IT PROVIDES CORRECT TIMING
• Install the overrun limit sensor magnet on a component, such as the crankshaft, that moves
independent of the resolver and whose motion is not affected by the condition of the resolver or
the resolver’s drive mechanism. Safe operation of the press depends on the overrun limit
sensor working correctly when the resolver or its drive mechanism fails.
• Install the overrun limit sensor magnet in the correct angular location according to the
instructions starting on page 2-82.
Failure to comply with these instructions will result in death or serious injury.
Make sure to position the overrun sensor
1/8 in. to 3/16 in. from the magnet
. This gap
specification is different from that of the flywheel speed sensor (see page 2-43).
DANGER
!
NOTICE