10
3.3 Remote reset
The BA377NE Timer or Clock's total display may be
remotely reset to zero by connecting terminals RS1
and RS2 together.
Permanent interconnection
inhibits
timing.
Remote
resetting
may
be
accomplished by any mechanically operated switch
located in Zone 2 as the Timer or Clock's reset
circuit is non incendive.
The reset switch and the
associated wiring should be able to withstand a
500V rms insulation test to earth.
A BA377NE may also be remotely reset from the
safe area. Any switch may be used. Fig 3 illustrates
how a BA377NE may be reset from both the safe
and the hazardous area.
The BA377NE total display may also be reset when
the
&
and
*
push buttons are operated
simultaneously in the display mode i.e. when the
instrument is displaying elapsed time. See 6.5.19
3.4
Control outputs (optional)
The BA377NE can be supplied with factory fitted
dual, solid state, single pole control outputs that may
be independently configured with normally open or
normally closed outputs.
CAUTION
Control outputs should not be used for
critical safety applications such as a shut
down system.
When the BA377NE Timer or Clock power supply is
turned off or disconnected, the control outputs will
open irrespective of whether normally open or
normally closed outputs have been selected.
Control output annunciators on the instrument
display indicate the status of each output.
If a
control output delay or silence time has been
selected the annunciator will flash during the delay
or silence period.
3.4.1 Solid state output
Each control output has a galvanically isolated
single pole solid state switch output as shown in
Fig 5. The outputs are polarised and current will
only flow in one direction.
Terminals A1 and A3
should be connected to the positive side of the
supply.
Ron
=
less than 5
Ω
+ 0.7V
Roff
=
greater than 1M
Ω
Note:
Because of the series protection diode some
test meters may not detect a closed control
output.
Fig 5 Equivalent circuit of each control output
Summary of Contents for BA377NE
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