- General Electric Computer Accessories User Manual

GEH-6385 Reference and Troubleshooting, 2300 V Drives Chapter 3 Paramters/Functions •
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• 3-33
Digital Inputs/Outputs and Mapping
Digital inputs and outputs provide an interface between the outside world and the
control. The ATB (terminal board) provides six general purpose digital inputs.
Three dry contact relays and one solid state relay driver are provided as outputs.
System and Local fault strings provide start and trip interlocks to the control.
Isolated digital inputs are listed with their associated terminal board points. A filter
debounces a noisy input signal. The filter should be set to zero in most instances,
since the hardware provides a level of debounce conditioning. The variables Digital
input 1 through Digital input 6 indicate the logical state of each digital input and are
used to interface to functions in the drive that require a Boolean signal.
Each relay output may be used by setting the parameters Relay 1 select through
Relay 3 select to the variables whose logical states are desired to drive the
corresponding relay. The associated terminal board points are shown for output
terminals of each relay. The variables Relay 1 state, Relay 2 state, and Relay 3 state
indicates whether the relay coils are energized.
Relay four is a solid-state relay driver that should be used for driving a 24 V dc, 10
mA relay. The relay driver output may be used by setting the parameter SS relay
driver sel to the variable whose logical state is desired to drive the relay. Solid state
relay indicates the status of the relay driver.
In addition to the four programmable outputs available on ATB, the drive provides 3
additional application outputs through the CTBC terminal board. The CTBC outputs
are not programmable but instead are mapped to some commonly used signals in the
drive. CTBC outputs are solid-state relay drivers that can be used for driving 24 V
dc, 10 mA relays. Signals available on CTBC are as follows:
CTBC Output Pre-programmed function
D08 (pins 33 & 35)
D07 (pins 29 & 31)
D06 (pins 25 & 27)
Closed when No trip fault is True
Closed when Running is True
Closed when No faults active is True
A pilot relay controls a main contactor. Most applications do not require a contactor
(see MA contactor absent). This contactor is normally controlled through drive
sequencing, but it may be controlled alternately by MA close req sel. The contactor
cannot be energized if either the Local Fault String or the System Fault String are
open. If the contactor is closed and the Local Fault String or the System Fault String
open, the contactor will be de-energized.
Contactor status feedback is available (MA contactor closed). MA contactor fbk
determines if the drive sequencer requires MA contactor closed to be active in
response to a contactor close command.
Related diagrams
• Digital Inputs / Outputs & Mapping (HWIO_Dig)