MSA 9010 LCD, Руководство по эксплуатации

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MSA AUER
MSA Configuration
Control Unit Models 9010 LCD and 9020 LCD 17
GB
5.7 Failure function
Beyond the red alarm LED's, the Control Units are equipped with a yellow LED [FAILURE] which
signals possible individual malfunctioning states [individual for each channel with 9020].
The nature of the failures, a listing of which is recorded in Section 9, is shown via the display.
The indication in a remote zone is accomplished via the related relay [FAILURE], which is
equipped with two free voltage-free N/O contacts [SPST] connected in series to each other in or-
der to guarantee the signalling.
In the ATEX version, the relay coil is normally energised.
With model 9020, the failure indication is common to the two channels when the indication
is predisposed with the relays or individual when predisposed with opto-isolated outputs.
A pre-existing alarm condition remains as such if the failure is subsequently detected,
while they are automatically blocked if the failure precedes the event that would have
caused it.
5.8 Alarms and overrange functions
Alarm Set points
The alarm set-points are designated as:
-
Caution [C] caution level
-
Warning [W] warning level
-
Alarm [A] alarm level
-
Overrange [EEEE] indication on the display of the full scale being exceeded
The exceeding of the alarm set-points will be displayed on the front panel via the red LED's and
causes the status of the opto-isolators and of the relays connected thereto to change.
The alarms can be configured via the various steps of Access Code 4, which, beyond setting the
intervention levels, enable the following choices:
-
alarms for rising signals or falling ones.
-
coils of the excited relays or unexcited ones in the non-alarm state.
-
resetting of the manual alarm state, as per mode 1M or 2M, or automatic with mode 1A or 2A.
[see the attachment].
The horn cut-out and the manual reset of the alarms is carried out the same using the UP and
DOWN keys of the front panel or with the external pushbutton, possibly connected to the back ter-
minal board, see EXTERNAL CONNECTIONS DIAGRAM.
When the offset and full-scale values change, the Control Unit 9010/20 configures the sets
of alarms as default ones; the default values of the sets of alarms should be considered in
a percentage of the range of measure.
In a manner limited to the ATEX version, the alarm set-points A and W are set from 1 to 80 %
of full scale, while the alarm set-point C is set from 1 to 100 % of full scale; the indication
of overrange is always connected and the alarms are configurable only on the rise.
The oxygen analysis can also occur in ATEX mode [%Vol], with a full scale 0-25%Vol and
with alarms without setting; the input signal in ATEX mode must originate from a 4/20 mA
transmitter, likewise ATEX certified [e.g. MSA/AUER DF 9500 transmitter].
In the non-ATEX version, with the unit of measure PPM it is possible to set average alarms
on 15 min [STEL] and/or on 8 hours [TWA].
The value of the STEL average will be available after 15 minutes from start-up or after 15 minutes
from the STEL setting in Access Code 4, step 14 [and/or step 18]. The sampling time for the cal-
culation of the averages is 1 minute.