6 Safety Functions When an Abnormality/Error Occurs
The STP pump is provided with safety functions for various abnormalities/errors (See Tables 6.3 and 6.4, "Safety Functions").
For troubleshooting, see Section 6.2, "Restarting After Any Safely Function Operates" and Section 15, "Troubleshooting."
6.1Safety Functions
6.1.1Power Failure
<Operation at a Power Failure>
When power voltage drops below 170 V due to a power failure, internal battery of the STP control unit automatically activate to supply power to the STP pump in order to maintain normal function of the magnetic bearing (backup operation during a power failure).
1)The STP control unit detects any power failure of 2 seconds or more and automatically switches to the BATTERY OPERATION mode and the STP pump decelerates. Gases are introduced from the emergency vent. valve at approx. 7000 rpm and the rotor lands on the touch down bearing and stops at approx. 2000 rpm.
In the BATTERY OPERATION mode, the "BATTERY OPERATION" lamp and the "EMERGENCY OPERATION" lamp light, and an alarm signal is output from I/O TB2 ALARM OUT terminals (10) – (9), (10) – (11) regardless of MANUAL or REMOTE OPERATION mode.
When the rotor lands on the touch down bearing, the "BATTERY OPERATION" lamp and the "EMERGENCY OPERATION" lamp go out, and the alarm output is reset.
2)In case of a power failure of less than 2 seconds, the STP control unit does not detect it and the STP pump continues rotating.
