7.24
SEL-351A Relay Instruction Manual Date Code 20080213
Inputs, Outputs, Timers, and Other Control Logic
Multiple Setting Groups
but not long enough to be qualified by time setting TGR in order to change the
active setting group to setting Group 4. For such a rotating selector switch
application, qualifying time setting TGR is typically set at 180 to 300 cycles.
Set TGR long enough to allow the selector switch to pass through
intermediate positions without changing the active setting group, until the
switch rests on the desired setting group position.
Selector Switch Switched to Position 5
Refer to Figure 7.22.
If the selector switch is rested on position 5 in Figure 7.21, setting Group 5
becomes the active setting group (after qualifying time setting TGR; Relay
Word bit SG5 = logical 1). Inputs IN101 and IN103 are energized and IN102 is de-
energized:
SS5 = IN103 * !IN102 * IN101 = IN103 * NOT(IN102) * IN101
= logical 1 * NOT(logical 0) * logical 1 = logical 1
To get from position 5 to position REMOTE on the selector switch, the switch
passes through the positions 4, 3, 2, and 1. The switch is only briefly in the
these positions, but not long enough to be qualified by time setting TGR to
change the active setting group to any one of these setting groups.
Selector Switch Now Rests on Position REMOTE
Refer to Figure 7.22.
If the selector switch is rested on position REMOTE in Figure 7.21, all inputs
IN101, IN102, and IN103 are de-energized and all settings SS1–SS6 in Table 7.7
are at logical 0. The last active setting group (Group 5 in this example)
remains the active setting group (Relay Word bit SG5 = logical 1).
With settings SS1–SS6 all at logical 0, the serial port GROUP command or
the front-panel {GROUP} pushbutton can be used to switch the active setting
group from Group 5, in this example, to another desired setting group.
Courtesy of NationalSwitchgear.com
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