Using the IntelliLogger™
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voltage is fixed at 5VDC (+/- 150mV). A typical variation in output voltage as a function of
load is 25mV (over a load range from 1 to 50mA).
For applications requiring reference or excitation voltage stability exceeding this spec (e.g.
bridge measurements), the actual output voltage can be sampled using an analog input
channel at the time that the excited sensor output is measured. The excitation voltage can
then be normalized (i.e. volts of signal per volt of excitation) within the Program Net.
D
IGITAL
O
UTPUTS
Two digital (on/off) outputs are provided on the System Base. The state of these outputs is under
software control via the Program Net.
L
OAD
C
ONNECTIONS
Connections for these two outputs, labeled
DO_A
and
DO_B
are made on the top terminal
strip terminals 12, 13 and 14. Terminal 13 is a shared circuit ground terminal (GND). Output
DO_A load should be connected from terminal 14 ( + ) to 13 ( - ) and Output DO_B load
across terminals 12 ( + ) and 13 ( - ).
O
UTPUT
C
HARACTERISTICS
The Digital Output terminals switch between 5VDC and 0VDC under Program Net control.
The outputs are short-circuit protected and can be shorted indefinitely without damage.
Protection circuitry in series with the outputs limits the drive current and the output voltage will
drop as a function of the delivered current. An effective 200 ohm series source resistance can
be used for calculation of the supplied voltage for user applications. For example, with a load
that draws 5mA of current, the output voltage will be approximately 5V - (0.005 x 200) = 4V
R
ELAY
O
UTPUTS
Two ‘Form C’ relays are provided on the System Base. The state of these relays is under
software control via the Program Net.
L
OAD
C
ONNECTIONS
Connections for the two relays, labeled RO_A and RO_B are made on the lower terminal strip,
terminals 1 through 6. The relay terminals are floating and not connected to internal
IntelliLogger power or ground. Each relay has Common (C), Normally Open (NO) and
Normally Closed (NC) contacts brought out to the terminal strip.
S
WITCHING
C
APACITY
The relay switching capacity is 1A ac/dc, 32V maximum.
R
ELAY
E
NERGIZED
LED
INDICATORS
A red LED indicator is provided on the front panel for each of the relays. When the indicator is
Off, the relay is not energized and continuity exists between the Com and the NC terminals.
When On, continuity exists between the Com and the NO terminals.
