Control Microsystems SCADAPack 350, Hardware Manual

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8 Digital Inputs
The SCADAPack 350 I/O Module provides eight universal digital inputs and outputs. The inputs are
for use with dry contacts such as switches and relay contacts. The SCADAPack 350 provides the
wetting current for the contacts.
If LED power is enabled, the SCADAPack 350 continuously sources approximately 5mA wetting
current into each dry contact input. Indicator LEDs will be at their maximum brilliance if on. This
facilitates field service and diagnostics.
If LED power is disabled then the wetting current is turned on only when the digital inputs are
scanned by the SCADAPack 350. Indicator LEDs are dim in this condition. This is normal.
Refer to the appropriate software manual for information on using the SCADAPack 350 Digital
Inputs and Outputs in application programs. For TelePACE applications refer to the Register
Assignment for SCADAPack 350 I/O module and for ISaGRAF applications refer to the I/O
Complex Equipment for SCADAPack 350 I/O.
The SCADAPack 350 I/O Module provides the following digital inputs.
Input Type Description
0 to 7 external
Dry contact inputs
.
These inputs are located on terminal P3.
0 = contact open (associated is LED off)
1 = contact closed (associated is LED on)
8 internal
VLOOP output status
0 = off
1 = on
See section
4.4.2-VLOOP Power Control
for details.
9 internal
DC/DC converter status
This bit reports the true status of the DC/DC converter. If
over-current causes the converter to be turned off, this bit
will clear.
0 = off
1 = on
See section
4.4.3- 12V to 24V DC/DC Converter Control
for details.
10 internal
VLOOP over-current status
Indicates VLOOP over-current has been detected. This input
clears when VLOOP output is off, or the over-current
condition clears.
0 = off
1 = on
See section
4.4.2.1- VLOOP Over-Current Protection
for
details.
11 internal
Digital output mismatch
Known outputs are compared to the corresponding inputs to
detect incorrect outputs. A point is compared if it has been
turned on at any time since controller reset. This input
indicates if one or more outputs mismatch. The source of the
mismatch can be determined by comparing each digital input
against the corresponding digital output.
0 = off
SCADAPack 350 Hardware Manual
February 14, 2007 22