Woodward MicroNet TMR 5009, Installation/Hardware Manual

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Manual 85580V2 5009 Installation/Hardware
Woodward 35
NOTES
Each main power supply provides three separate 24 Vdc outputs rated for 0–
6 A each. To preserve system integrity, it is recommended that the control’s
three isolated 24 Vdc outputs be kept isolated from each other at all times. If
the control’s 24 V power is used to power external devices, the system’s
three 24 V outputs must not be tied together. If these outputs are tied
together, and a short circuit occurs, it will shut down the entire 5009 control.
External devices requiring 24 Vdc power must be connected to only one of
the power supplies.
Externally powered analog inputs or outputs and external relay coil power
must be supplied by and IEC rated or NFPA 70 (NEC) Class 2 power supply
as required by local authority having jurisdiction.
Speed Sensor Inputs
The 5009 control uses speed sensing probes mounted off of a gear connected or
coupled to the turbine’s rotor to sense turbine rotor speed. Any of the control’s
four speed channels accept passive magnetic pickup units (MPUs), 12 Vdc
proximity probes, or 24 Vdc proximity probes. It is not recommended that gears
mounted on an auxiliary shaft coupled to the turbine rotor be used to sense
turbine speed. Auxiliary shafts tend to turn more slowly than the turbine rotor
(reducing speed sensing resolution) and have coupling gear back-lash, which
results in less than optimum speed control. For safety purposes it is also not
recommend that the speed sensing device sense speed from a gear coupled to a
generator or mechanical drive side of a system’s rotor coupling.
An application may use any combination of the accepted speed probes. All
speed sensing inputs use the same programmed gear ratio and number of teeth
to calculate speed, thus the speed probes used should sense speed from the
same gear. The 5009 control can sense and control turbine speed from a single
speed probe, however, it is recommended that all applications use multiple
speed probes to increase system reliability.
A passive MPU provides a frequency output signal corresponding to turbine
speed by sensing the movement of a gear’s teeth past the MPU’s pole piece.
The closer the MPU’s pole piece is to a gear’s teeth and the faster the gear turns
the higher a passive MPU’s output amplitude will be. The 5009 control must
sense an MPU voltage of 1 to 25 Vrms for proper operation.
Depending on an MPU’s limitations, each input channel can be jumper
configured to allow an MPU to drive either two or three inputs (some MPUs
cannot drive three inputs). Wire jumpers must be installed to allow an MPU to
drive into all three inputs. When the jumpers are not installed, only two input
modules are driven by a MPU. With proper MPU, gear size, and MPU-to-gear
clearance, speed measurement should be capable down to 100 Hz. Standard
MPU clearance is recommended to be 0.25 to 1.02 mm (0.010 to 0.040 inch)
from tooth face to pole piece. For information on selecting the correct MPU or
gear size, please refer to Woodward manual 82510. See Figure 4-2 for wiring
schematic.
A proximity probe may be used to sense very low speeds. With a proximity
probe, speed can be sensed down to 0.5 Hz. The 5009 control can be
programmed to turn on or off a turbine turning gear using a relay output
programmed as a speed switch. See Figure 4-3 for proximity probe wiring
schematic.