Emerson Rosemount 936, Reference Manual

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Temperature range
-67 to 149 °F (-55 to 65 °C)
Immunity to false alarm
Does not produce a false alarm and is not influenced by solar radiation, hydrocarbon
flames, or other external infrared radiation sources.
4.2 Electrical specifications
Operating voltage
18-32 Vdc
Power consumption
Table 4-2: Detector and Source Maximum Power Consumption
Without heated optic (max.) With heated optice (max.)
Detector 150 mA 300 mA
Source 200 mA 300 mA
Electrical input protection
The input circuit is protected against voltage-reversed polarity, voltage transients, surges,
and spikes, according to EN50270.
Electrical outputs
• 0-20 mA current output: The 0-20 mA is an isolated sink option. You can also configure
this output as source (see
Wiring configurations ).
The maximum permitted load resistance is 500 Ω.
• Communication network: The detector is equipped with an RS-485 communication
link that can be used in installations with computerized controllers.
Communication is compatible with the Modbus
®
protocol.
— This protocol is standard and widely used.
— It enables continuous communication between a single standard Modbus controller
(master device) and a serial network of up to 247 detectors.
— It enables connection between different types of Rosemount detectors or other
Modbus devices to the same network.
• HART
®
protocol: A digital communication protocol used to communicate between
intelligent field instruments and the host system.
Through the HART protocol, the detector can:
— Display setup.
— Reconfigure setup.
— Display and determine the detector status.
— Perform detector diagnostics.
Specifications Reference Manual
October 2021 00809-0100-4036
26 Emerson.com/Rosemount