Honeywell RMA 3000, Руководство пользователя

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20 34-ST-25-19 RMA 3000 Remote Meter Assemblies User Manual Release 1
6/04
Installation in Non-Hazardous Locations
When installed in ordinary, non-hazardous locations, wiring shall comply with National Electrical Code
(NEC) or with local electrical code requirements.
Multiple Remote Meters
The Honeywell-certified engineering drawings of wiring configurations that have been approved by FM,
CSA, CENELEC, and ATEX include only configurations that include a single meter (SM, DM, or ME)
with a single Honeywell ST 3000 Pressure Transmitter.
However, the Honeywell remote meter housing provides a convenient means of connecting multiple meters
to a single transmitter in non-hazardous locations.
Series-Connected Meters
As mentioned under Meter Types – Options near the beginning of this manual, the SM and the ME are
current-oriented, series-connected devices. Multiple meters (any combination of SM and ME) may be
connected to a given transmitter, provided that the following condition is met.
Voltage
Pwr Supply
≥
Minimum Terminal Voltage
Transmitter
+ Number of SMs (2.3 volts) + Resistance
Total Loop
(22 mA)
NOTE: Total loop resistance must include wiring and cabling as well as for associated
apparatus such as barrier devices and control equipment such as Field Terminal
Assembly (FTA) and FTA cabling.
Parallel-Connected Meters
As mentioned under Meter Types – Options near the beginning of this manual, the Digital Enhanced
meter (DM) is a voltage-oriented device that is connected in parallel to a transmitter.
Each DM draws 0.5 mA of current. Several DM meters can be connected in parallel with the transmitter,
via the yellow wire (negative) and red (positive) wires, provided that the sum of the current loads imposed
by each DM in the loop does not exceed the capacity of the power supply.