GE 869 Instruction Manual page 452

MONITORING
NOTE:
NOTE:
4–320
The voltage threshold must be set to 17 V for the inputs to be recognized using the internal
+24 V.
The following figure illustrates three wiring examples: (a), (b) and (c) of a speed probe
connected to the input terminals. For illustration purposes, the breaker status inputs are
shown along with the speed probe input.
Example (a)An internal +24 V supply is used to power both the speed probe connected to
CI # 4 and the breaker status signals (DRY type) connected to CI # 1 and CI # 2 of the
same Slot F.
Example (b)An internal +24 V supply is used to power the speed probe connected to CI #
4 while an external DC power supply is used by the breaker status signals (WET type)
connected to CI # 1 and CI # 2. In this example, since both speed probe and breaker
status signals are connected to Slot F, the voltage threshold must be set to 17 V.
Example (c)Separate input slots are used for the speed probe input signals and the
breaker status. An internal +24 V supply is used to power the speed probe connected to
CI # 4 of Slot G, the voltage threshold must be set to 17 V. WET Breaker status signals are
connected to CI # 1 and CI # 2 of Slot F. The voltage threshold must be selected as per
the criteria: 17 V for 24 V sources, 33 V for 48 V sources, 84 V for 110 to 125 V sources
and 166 V for 250 V sources.
Figure 4-134: Wiring Examples of Speed Protection Input
The maximum load current that can be delivered by the internal +24 V supply is 80 mA.
When the internal +24 V supply is used to power the probe, the current limitations of the
24V supply must be considered.
RATED SPEED
Range: 100 to 7200 RPM in steps of 1
Default: 3600 RPM
RPM defines the rated speed of the motor.
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 4: SETPOINTS