Recommended Configuration - Emerson Oxymitter 4000 Instruction Manual

Oxymitter 4000
4-3

RECOMMENDED CONFIGURATION

a. 4-20 mA Signal Upon Critical Alarm
Rosemount recommends that the factory
default be utilized. The 4-20 mA signal will
go to the 3.5 mA level upon any critical
alarm which will cause the O
unusable. Customer can also select 21.6
mA as the failure setting if normal opera-
tions cause O
zero % O (4 mA) level. If the O
2
ment is being utilized as part of an auto-
matic control loop, the loop should be
placed into manual upon this failure event
or other appropriate action should be taken.
b. Calibration
Rosemount recommends utilizing an auto-
calibration system, actuated by the "calibra-
tion recommended" diagnostic. New O
cells may operate for more than a year, but
older cells may require recalibration every
few weeks as they near the end of their life.
This strategy ensures that the O
always accurate, and eliminates many un-
necessary calibrations based on calendar
days or weeks since previous calibration.
When utilizing the SPS 4000 or the IMPS
4000, consider wiring some or all associ-
ated alarm contacts.
1. CALIBRATION INITIATE. Contact
from the control room to an SPS 4000
or IMPS 4000 (one per probe) provides
the ability to manually initiate a calibra-
tion at any time from the control room.
Note that calibrations can also be initi-
ated from a HART handheld communi-
Rosemount Analytical Inc. A Division of Emerson Process Management
reading to be
2
readings to go below the
2
measure-
2
reading is
2
2. IN CALIBRATION. One contact per
3. CALIBRATION FAILED. One contact
2
4. 4-20 mA SIGNAL DURING CALI-
Instruction Manual
IB-106-340 Rev. 3.0
December 2003
cator, from Asset Management Solu-
tions software, or from the keypad on
the Oxymitter 4000.
probe provides notification to the con-
trol room that the "calibration recom-
mended" diagnostic has initiated an
automatic calibration through the SPS
4000 or IMPS 4000. If the O
being utilized in an automatic control
loop, this contact should be utilized to
place the control loop into manual dur-
ing calibration.
per probe from an SPS 4000 or IMPS
4000 to the control room for notification
that the calibration procedure failed.
Grouped with this alarm is an output
from a pressure switch which indicates
when the calibration gas bottles are
empty.
BRATION. The 4-20 mA signal can be
configured to respond normally during
any calibration, or can be configured to
hold the last O value upon the initiation
2
of calibration. Factory default is for the
4-20 mA signal to operate normally
throughout calibration. Holding the last
O value may be useful if several
2
probes are being averaged for the pur-
pose of automatic control. Unless sev-
eral probes are being averaged, always
place any control loops using the O
signal into manual prior to calibrating.
Configuration with LOI
signal is
2
2
4-5