WÄRTSILÄ Vasa R22, Instruction Manual

Page: 287 / 297

23.2.3.4 C4, TC-card: Measuring converter for one or
two turbochargers
a) Theory of operation:
The sine wave signal of the turbocharger
speed sensor is amplified and transmitted to a squarewave
signal. This can be measured by frequency counter.
The square wave frequency signal is converted to a speed-
proportional voltage 0 - 10 V. This voltage is buffered and forms
the measuring voltage for the remote speed indicators.
The card may consist of two channels.
b) Adjustment procedures:
The analog output re-adjustment can
be done by means of the potentiometers P701 and P711.
P701 : nTC1
P711 : nTC2
When turning the potentiometer clockwise, the output will in-
crease and vice versa.
c) Technical specification:
Inputs:
Frequency: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0...8000 Hz
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . > 100 mVpp sine
Supply voltage:. . . . . . . . . . . . . . . . . . . . . . . . . . +12 V, 0, -12 V
Current consumption: . . . . . . . . . . . . . . . . . . . . . . . max 35 mA
Outputs:
Frequency: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Vpp
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 mA, short-circuit-proof
Voltage:. . . . . . . . . . . . . . . . 0...10 V, 15 mA, short-circuit-proof
Unlinearity: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
±
0.1 %
Temperature dependence:. . . . . . . . . . . . . . . . . . . . < 0.03 %/K
TC-card C4
21 22 23 20 6 11 14 2 15 13 17
f
U
f
U
f
n
f
n
+- 12VDC
+ -
n
TC2 TC1
n
n TC
P 711 P 701
Output 1 Output 2
Fig 23-5
2223578935
23 Instrumentation and Automation 22-9601
23 - 12 VASA 22