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875 Benzene Monitor MANUAL
Outputs and Communications
Titan has five communication outputs:
The on-board LCD and LEDs on the faceplate.
4-20mA Current Loop.
RS485 Modbus (simplex/half-duplex or fully-duplex),
USB (Accessible on the Detector Module).
Two programmable relays.
Titan monitors, in real-time, the current (Live) and the Short-Term Exposure Limit (STEL) benzene
concentration. The STEL is calculated over the previous 15 minutes.
This real-time information is displayed on the LCD and transmitted on the 4-20mA and RS485 channels.
You can program two alarms to operate at a chosen concentration of benzene and/or a chosen STEL limit. The
alarms will display a message on the LCD and LEDs; energize the relays: and transmit a signal on the 4-20mA
channel.
The alarms and relays are individually programmable to the settings required by the site policy. You can choose
either alarm to energize either relay. The default settings would be:
Alarm 1: 5.0ppm live
Alarm 2: 0.5ppm STEL
Relay 1: Alarm 1, N/O
Relay 2: Alarm 2, N/O
Both relays can be programed to be Normally Open or Normally Closed. They can switch 24VDC at 1.5A
maximum load. When the Titan is not powered the default state of relay 1 is N/C, the default state of relay 2 is
N/O
Data is stored internally for a minimum of two years and can be downloaded with TitanPC software via USB or
RS485 for analysis and archive storage.
You can configure the RS485 connection for half-duplex, 2-wire, or full-duplex, 4-wire, communication. Refer to
Installation,
Terminal
Block-2.
The 4-20mA output fault indications are given by discrete current signals between 2.0 and 3.5mA. Refer to the
table in Fault Diagnostics,
Fault
Conditions.
Page 17 of 65
Ion Science Ltd.
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