EndRun TDC3303, User Manual

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T D C 3 3 0 3 U s e r M a n u a l 10
C H A P T E R T H R E E
11 T D C 3 3 0 3 U s e r M a n u a l
C O N T R O L A N D S T A T U S C O M M A N D S
disablemode
This command allows you to select external alarm inputs from the reference source (if any) as speci-
fied in Appendix D. (These inputs are labeled “DISABLE IN” on the rear-panel.) When the external
alarm input is asserted it will disable the corresponding reference signal input and/or set a system
alarm. If you are not using external alarms then set disablemode=n,n.
The
disablemode
syntax is
disablemode=a,b,x
where Parameter
a
may be Y (yes) or N (no) for
whether to use the Disable A input or not. Parameter
b
may be Y or N for whether to use the Dis-
able B input or not. (Depending upon the
switchmode
setting, either the
a
or
b
setting could be a
“don’t care” and would be ignored. For example, if
switchmode=a
, then parameter
b
in the
dis-
ablemode
command would be ignored.) Parameter
x
tells the chassis what action to take when there
is no good input signal to switch to.
x
=ON to leave the last selected input switched on, or
x
=OFF
to switch the last selected input off. This parameter can be left blank if both disable inputs are to be
ignored.
If
disablemode=n,n
the chassis will ignore the Disable A and Disable B inputs.
If
disablemode=y,y,off
(or
n,y,off
or
y,n,off
) the chassis will turn off the reference input
when it sees the disable input asserted and there is no good signal present on the other signal input.
For example:
Example 1: If
disablemode=y,n,off
and
switchmode=a
then there is no secondary reference
input and the chassis cannot switch if the Disable A input is asserted. If Disable A is asserted, Input A
will be switched off, which will turn off all the outputs.
Example 2: If
disablemode=y,y,off
and
switchmode=ab
and the Disable A input is asserted,
the chassis will attempt to switch to Signal Input B. However, if Signal Input B has a fault condition
(input signal goes away or Disable B is asserted) then Signal Input A will be switched off, which will
turn off all the outputs.
Once both inputs have been switched off then you must use the
return
command to restore the unit
to a normal operating condition.
If
disablemode=y,y,on
(or
n,y,on
or
y,n,on
) then the chassis will switch between the primary
and secondary inputs as described above when the disable input is asserted. In this example the chas-
sis will not switch the signal input off as described above, but will leave the signal input switched on.
This will leave all the outputs on.
Typing
disablemode
by itself, with no parameters, will display the current setting.
If you change this setting it will be saved in non-volatile memory. This is a configuration command
and if the parameters are changed this will cause a re-initialization of the software.
Set:
disablemode=y,n,on
Chassis response:
OK
(Disable A is valid and Disable B is ignored. The
chassis will leave the inputs on if Disable A is
asserted.)