CTI EM2 Series, Инструкция по установке и эксплуатации

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4
EM2
General Description Installation
This manual covers the EM2-24 and EM2-120 entrance
monitors. The EM2-120 includes an installed AC-
DC power supply that allows for 120Vac input and
converts it to 24Vdc power for the EM2.
The EM2 terminates the gas sensor’s 4-20 mA signal,
and re-transmits the 4-20 mA signal to another analog
input device such as gas detection controller or plant
PLC. If no connection is made to the signal output
terminal, the unit will act as a stand-alone device.
Multiple entrance monitors can be installed in series,
providing flexible remote viewing options.
The EM2 provides continuous real-time monitoring of
the sensor. Gas concentrations and alarm status are
indicated on the monochrome LCD display.
The EM2 is assembled into a wall mounted enclosure
designed for non-classified locations. The gas sensor
(not included) is installed at the location where gas is
to be detected. The total distance between the sensor
and EM2, and the EM2 and the power supply should
not exceed 1,000 ft.
A calibration mode setting allows for sensor
maintenance and calibration without tripping the
relay and locks the analog output signal at 4 mA. The
onboard relay has adjustable on/off time delays to
prevent unnecessary cycling during a fault or alarm
condition.
Locating the Entrance Monitor
The EM2 can be installed indoors or outdoors and
should be installed for easy viewing and accessibility
by operating personnel.
Installation Guidelines:
• Mount on solid surface with minimal vibration.
• Mount readout in a general-purpose location only.
Do not install in a hazardous environment.
• Mount readout away from electromagnetic
interference.
• Protect readout from physical damage.
• If mounting on a wall with studs, the mounting
screws should be screwed into the studs.
Figure 1:
Dimensions
3.94"
6.0"
5.59"
6.1"
2.8" deep (EM2-24)
4.2" deep (EM2-120)