7.11
Date Code 20060320 Instruction Manual SEL-311C Relay
Inputs, Outputs, Timers, and Other Control Logic
Remote Control Switches
Remote Control Switches
Remote control switches are operated via the serial communications port only
(see CON Command (Control Remote Bit) on page 10.37).
The switch representation in this figure is derived from the standard:
Graphics Symbols for Electrical and Electronics Diagrams IEEE Std 315-1975,
CSA Z99-1975, ANSI Y32.2-1975, 4.11 Combination Locking and Nonlocking Switch,
Item 4.11.1.
Figure 7.10 Remote Control Switches Drive Remote Bits RB1 Through RB16
The outputs of the remote control switches in Figure 7.10 are Relay Word bits
RBn (n = 1–16), called remote bits. Use these remote bits in SEL
OGIC control
equations.
Any given remote control switch can be put in one of the following three
positions:
➤ ON (logical 1)
➤ OFF (logical 0)
➤ MOMENTARY (logical 1 for one processing interval)
Remote Bit
Application Ideas
With SELOGIC control equations, the remote bits can be used in applications
similar to those that local bits are used in (see Local Control Switches on
page 7.7).
Also, remote bits can be used much as optoisolated inputs are used in
operating latch control switches (see discussion following Figure 7.15). Pulse
(momentarily operate) the remote bits for this application.
Remote Bit States
Not Retained When
Power Is Lost
The states of the remote bits (Relay Word bits RB1–RB16) are not retained if
power to the relay is lost and then restored. The remote control switches
always come back in the OFF position (corresponding remote bit is deasserted
to logical 0) when power is restored to the relay.
Remote Bit States
Retained When
Settings Changed or
Active Setting Group
Changed
The state of each remote bit (Relay Word bits RB1–RB16) is retained if relay
settings are changed (for the active setting group or one of the other setting
groups) or the active setting group is changed. If a remote control switch is in
the ON position (corresponding remote bit is asserted to logical 1) before a
setting change or an active setting group change, it comes back in the ON
position (corresponding remote bit is still asserted to logical 1) after the
change. If a remote control switch is in the OFF position (corresponding
Logical 1
RBn
(n = 1 through 16)
ON Position
(Maintained Logical 1
Position)
OFF Position
(Maintained Logical 0 Position)
MOMENTARY Position
(Logical 1 for One Processing Interval)
Relay
Word
Bit
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