BE1-951 Input
and
Output Functions
3-7
SG-IN Command
Purpose:
Read or set contact sensing input recognition and debounce.
Syntax:
SG-IN<x>[=<Recognition Time>,<Debounce Time>]
Comments: x = input number 1, 2, 3, or 4. Omitting n will read or set parameters for all inputs. See Table
3-3 for SG-IN settings information.
SG-IN Command Example
1.
Read the conditioning settings for input 3.
>SG-IN3
4,16
If you are concerned about ac voltage being coupled into the contact sensing circuits, the recognition time
can be set to greater than one-half of the power system cycle period. This will take advantage of the half-
wave rectification provided by the input circuitry.
If an ac wetting voltage is used, the recognition time can be set to less than one-half of the power system
cycle period and the debounce timer can be set to greater than one-half of the power system cycle period.
The extended debounce time will keep the input energized during the negative half-cycle. The default
settings of 4 and 16 milliseconds are compatible with ac wetting voltages.
Retrieving Input Status Information From the Relay
Input status is determined through HMI screen 1.4.1 or through the communication ports using the RG-STAT
(report general-status) command. See Section 6,
Reporting and Alarm Functions, General Status Reporting
for more information.
OUTPUTS
BE1-951 relays have five general purpose output contacts (OUT1 through OUT5) and one fail-safe, normally
closed (when de-energized), alarm output contact (OUTA). Each output is isolated and rated for tripping
duty. OUT1 through OUT5 are Form A (normally open) and OUTA is Form B (normally closed).
Hardware Outputs and Virtual Outputs
Output contacts OUT1 through OUT5 and OUTA are driven by BESTLOGIC expressions for VO1 through
VO5 (virtual outputs 1 through 5) and VOA (virtual output A). The use of each output contact is completely
programmable so you can assign meaningful labels to each output and to the logic 0 and logic 1 states of
each output. Section 7,
BESTlogic Programmable Logic has more information about programming output
expressions in your programmable logic schemes.
A virtual output (VOn) exists only as a logical state inside the relay. A hardware output is a physical output
relay contact. BESTLOGIC expressions for VO1 through VO5 (virtual outputs 1 through 5) and VOA (virtual
output A) drive output contacts OUT1 through OUT5 and OUTA. The state of the output contacts can vary
from the state of the output logic expressions for three reasons.
1.
The relay trouble alarm disables all hardware outputs.
2.
The programmable hold timer is active.
3.
The select-before-operate function overrides a virtual output.
Figure 3-2 shows a diagram of the output contact logic for the general purpose output contacts. Figure 3-3
illustrates the output contact logic for the fail-safe alarm output contact.
