Technical Manual

3. ELECTRICAL DESCRIPTION
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LZT 123 7607 R1B
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Digital Inputs
The digital input IN-1 is available on pin 3 of the RJ12 connector. Its state
is detected by IO5 of the embedded GR47 engine, see GT47-GR47 signal
cross reference table, page 21.
The distinction between low level and high level signals is at the voltage
level of 3 V. Voltages above 3 V are detected as high level voltages and
voltages below 2.8 V are detected as low level.
Digital Outputs
The RJ12 power supply connector has two different output drivers:
• OUT-1 is driven by a high side switch that applies V
IN
to pin 5 of the
RJ12 connector. IO1 of the embedded GR47 engine is used to activate
the OUT-1 signal, see GT47-GR47 signal cross reference table,
page 21.
• OUT-2 is driven by a low side switch that shorts pin 2 of the RJ12
connector to ground when activated. IO3 of the embedded GR47
engine is used to activate OUT-2, see GT47-GR47 signal cross
reference table, page 21.
V
IN
Monitoring
The voltage, V
IN
, can be monitored internally by the GT47, for example if
the control terminal is supplied from an external battery. ADC1 on the
GR47 is used for this purpose, see GT47-GR47 signal cross reference table,
and is calibrated to operate in the voltage range 0 – 31.875 V. The
resolution of the 8 bit converter, ADC1, provides a measurement accuracy
of approximately 3%.