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Logic interface item
Type Open collector transistor plus pull up
resistor. Refer to Figure: Interface circuits
for nEXT turbo pump controllers on page
27.
< Normal speed (default 80%)
O (2.2 kW pull up to 12 V d.c.)
³ Normal speed
On (< 0.8 V d.c. sinking 20 mA)
Current rang 20 mA to 0 V
Voltage rang 28.8 V d.c. maximum external pull up
voltage
Fail status output:
Type Open collector transistor plus pull up
resistor. Refer to Figure: Interface circuits
for nEXT turbo pump controllers on page
27.
Fail
O (3.3 kW pull up to 12 V d.c.)
OK On (< 0.1 V d.c. sinking 1.7 mA,
< 0.8 V d.c. sinking 20 mA)
Current rang 20 mA to 0 V
Voltage rang 28.8 V d.c. maximum external pull up
voltage
*
Mang half of connector not supplied.
Refer to the table that follows for the logic interface connector pins for the electrical
connecons.
Table 7 Logic interface connector pins
Pin
Number
Signal Polarity Use
2 0 V Control reference -
0 V reference for all control and status
signals below.
3
START / STOP control
input
- Connect to Pin 2 to start pump
4
STANDBY control
input / Serial RX / RS485
A-
-
Connect to Pin 2 to enable standby
speed when serial enable is inacve
and RS485 / RS232 switch is in the
RS232 posion.
5 Serial enable -
Connect to Pin 2 to enable the serial
link
7
FAIL / Serial TX / RS485 B
+
-
Logic high when fail condion exists
and serial enable is inacve and
RS485 / RS232 switch is in the RS232
posion.
9 Analogue output Posive
0 ‑ 10 V output proporonal to
measured output
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B8G000880_D - Technical data