7 SAFETY FUNCTIONS
The STP pump has safety functions for various abnormities/errors.
When abnormities/errors are detected, the "STATUS" LED flashes in red or orange (except during
deceleration). If an abnormality/error is found when using the STP pump, check it and take measures
in accordance with the following procedures. If there are no relevant trouble cases, or if the system
does not work correctly even after the measures have been taken, see Section 8.5.
7.1 Safety functions
7.1.1 Power Failure
When the power voltage drops below 160 V due to a power failure, the rotation with the magnetic
bearing is maintained using the regenerative energy of the rotor if the rotational speed is high.
(backup operation during a power failure)
The lowest rotational speed to which the magnetic bearing can operate at a power failure is called a
backup rotational speed.
1. When the rotational speed is about 5,000 rpm or more at a power failure:
If the STP pump detects any power failure of 2 seconds or more, it decelerates. At this time, the
"STATUS" LED flashes in red. In the case of the I/O Remote interface, a failure signal also
simultaneously outputs from FAILURE OUT pins (14)-(33) and (15)-(33) of the "X4 REMOTE"
connector.
When the rotational speed goes down to about 5,000 rpm, the rotor lands on the touch down
bearing and stops. Then "STATUS" LED is extinguished.
If the STP pump does not detect a power failure of fewer than 2 seconds, the STP pump will
continue to rotate.
Moreover, the STP pump does not detect a power failure during decelerating.
2. When the rotational speed is less than about 5,000 rpm at a power failure:
The STP pump does not detect the power failure. The rotor lands on the touch down bearing
and stops.
Table 33 shows the states of LED output and the "X4 REMOTE" output signals at a power failure.
To Next Page
Loading...
Need help?
General
