Honeywell 5704 Operating Instructions Manual page 189

MAN0448_Issue 13_ 01-2010
005704-M-5001 A03249
CHAPTER 10 -SPECIAl CONDITIONS FOR SAFE USE ACCORDING
TO EC-TyPE ExAMINATION CERTIFICATE BVS 04 ATEx G 001 x
The following special properties have to be considered at operation of
the control unit:
- When operated with remote sensors with 4-20 mA
interface the specifications of the 4-20 mA interface and
the behaviour below 4 mA and above 20 mA have to be
considered.
- The parameters "A/D-average" and "signal filter" shall
be set to the sensor-specific default values. Other settings
shall only be used in exceptional, justified circumstances
and with the manufacturer's permission. For both
parameters, the lowest settings shall be used which are
possible for the application.
- When configuring the control cards, the sensor specific
default settings should be used for the error codes "ER80",
"ER81", "ER87" and "ER88" (parameters "signal over
range", "signal under range", "fault over range" and "fault
under range").
- The error codes "ER87", "ER88" and "ER81" (parameters
"fault over range", "fault under range" and "signal under
range") shall be set latching.
- When operated with remote sensors (e.g. Sensepoint)
which may deliver signals within the measuring range at
concentrations above the measuring range, the error
code "ER80" (parameter "signal over range") shall be set
latching. If the parameter is set below the default value
all alarm relays shall be configured in such a way that
alarming also takes place in the presence of faults.
- For remote sensors with 4-20 mA interface the parameters
"signal over range" and "fault over range" shall be set in
such a way that during normal operation (including the
application of 100 % gas to the remote sensor) "ER80"
can be activated but not "ER87".
- The analogue outputs should be operated with live zero
(4-20 mA setting). The "< 4 mA clipping" feature should
be activated only in exceptional cases.
- Irrespective of the operating mode of the analogue output,
the "fault level" and "inhibit level" shall be configured to
different values outside the measuring range. The
signalling of faults and inhibits at the analogue output
shall be activated.
- If no local inhibit relays are configured, a master inhibit
relay shall be configured.
- If no local fault relays are configured, a master fault relay
shall be configured.
10 - 2
5704 Control System