23.3.1.2 Testing of the overspeed trip by using a signal
generator
1 Connect the signal generator (848113)
to both speed
sensors one at a time. The signal generator is connected to the pins
signal and gnd of the speed sensor. See the Fig 23-26 for connec-
tions. The overspeed stop should be detected when the overspeed
limit is exceeded.
Note!
To avoid lubrication shut down when simulating engine speed
on a standstill engine the pressure transmitter PT201-1 and
pressure switch PSZ201 can be disconnected. See installation
specific electrical drawings for connections.
2 Increase the frequency
of the input signal.
3 Check at what frequency
the overspeed is detected.
The speed is detected from the camshaft gear. The rotation speed of
the camshaft gear is half of the engine rotation speed. The frequency
corresponding to the overspeed can be easily calculated when the
teeth number of the camshaft gear is known. In an engine with
planetary gear the camshaft gear has 42 teeth. In an engine without
planetary gear the camshaft gear has 48 teeth.
The following formula gives the frequency detected by the
sensor corresponding to engine speed:
Frequency
(
Hz
)
=
æ
ç
è
Speed
[
rpm
]
2
ö
÷
ø
æ
ç
è
Teeth
Number
60
ö
÷
ø
The frequency corresponding to the engine speed is shown in
tables below with engine nominal speed of 720 rpm and 750 rpm
accordingly.
Table 23-1
Frequency corresponding to
speed
No planetary gear
Planetary gear
720 rpm (nominal speed)
288 Hz
252 Hz
828 rpm (15% overspeed
limit, DCU/SMU)
331 Hz
290 Hz
850 rpm (18% overspeed
limit, RM)
340 Hz
297 Hz
23
Instrumentation and Automation
32-200115/II
23-8
WÄRTSILÄ 32
Summary of Contents for VASA 6L32
Page 4: ......
Page 18: ...Appendix B Welding Precautions 200640 00 6...
Page 26: ...01 Main Data Operating Data and General Design 32 200634 01 01 8 W RTSIL 32...
Page 60: ...Appendix A Environmental Hazards 200507 02A 10...
Page 68: ...Page 7 7 Document No 4V92A0645 Rev j...
Page 84: ...03 Start Stop and Operation 32 200402 04 03 12 W RTSIL 32...
Page 98: ...04 Maintenance Schedule 32 200623 01 04 14 W RTSIL 32...
Page 154: ...07 Tightening Torques and Use of Hydraulic Tools 32 200643 01 07 30 W RTSIL 32...
Page 162: ...08 Operating Troubles Emergency Operation 32 200402 01 08 8 W RTSIL 32...
Page 164: ...Specific Installation Data 2005 01 09 2...
Page 178: ...10 Engine Block with Bearings Oil Sump and Cylinder Liner 32 200150 10 14 W RTSIL 32 34SG...
Page 216: ...Appendix A Testing of cylinder tightness 32 200142 A 4 W rtsil 20 32 34...
Page 226: ...13 Camshaft Driving Gear 32 200546 02 13 10 W RTSIL 32...
Page 254: ...15 Turbocharging and Air Cooling 32 200549 10 15 20 W RTSIL 32...
Page 274: ...16 Injection System 32 200627 01 16 20 W RTSIL 32...
Page 280: ...Fuel System 32 200508 07 17 6 W RTSIL 32...
Page 314: ...19 Cooling Water System 32 200050 19 14 W RTSIL 32...
Page 394: ...23 Instrumentation and Automation 32 200115 II 23 60 W RTSIL 32...