Woodward Vertex-Pro, Инструкция по установке/руководство по оборудованию

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Vertex-Pro Motor-Driven Compressor Control Manual 26489V1
54 Woodward
Analog Outputs
The analog outputs are 4–20 mA with a full-scale range of 0–25 mA. Each output
monitors the output source current for fault detection. All of the analog outputs
may be individually disabled. When a channel fault or a module fault is detected,
the application program may annunciate the fault, disable the channel or module,
and stop using the data in system calculations or control.
The Analog Combo module has four 4–20 mA current output drivers. All analog
outputs can drive a maximum load of 600 ohms (load + wire resistance). Care
should be taken to prevent ground loops and other faults when interfacing to non-
isolated devices. See Figure 9-19 for an example of 4–20 mA output wiring.
Actuator Outputs
The actuator outputs may be configured for 4–20 mA or 20–160 mA.
Configuration is done through the application software; no hardware
modifications in the forms of jumpers or switches are necessary. For fault
detection, each output monitors the output source current and the output return
current. All of the actuator outputs may be individually disabled. When a channel
fault or a module fault is detected, the application program may annunciate the
fault, disable the channel or module, and stop using the data in system
calculations or control.
Dither may be provided in the application software for each output. Dither is a low
frequency (25 Hz) signal consisting of a 5 millisecond pulse modulated onto the
DC actuator-drive current to reduce sticking due to friction in linear type
actuators. Woodward TM-type actuators typically require dither. Dither amplitude
is variable through the application software. See Figure 9-19 for an example of
actuator wiring.
For a dual coil actuator in a simplex system, two actuator driver
outputs must be used.
Configuration Notes

Maximum impedance for a 4 to 20 mA actuator output driver is 360 ohms
(actuator imp wire resistance).

Maximum impedance for a 20 to 160 mA actuator output is 45 ohms
(actuator imp wire resistance).

Each actuator driver senses its source and return current to allow
overcurrent and undercurrent alarms and shutdowns.
7.4.4—FTM Reference
See Chapter 8 for complete Analog Combo FTM field wiring information. See
Appendix A for proper Module, FTM, and cable part numbers.