CTI EM2 Series, Инструкция по установке и эксплуатации

Страница: 6 / 24

6
EM2
Sensor Wiring:
• 4-20 mA, 261 Ohm input impedance.
• Refer to sensor manual for cable recommendations
(typically 18/3 shielded cable (General Cable
#C2535A or equivalent)).
• Cable should not exceed 1,000 feet total length
from the sensor to the power supply.
Relay Wiring:
• AC wiring must be run in separate conduit from the
sensor cables, if length of run is more than 10 ft.
• If a separate relay cable conduit hole is needed, do
not drill or punch hole on hinge sides of enclosure.
• The alarm relay has Form C dry contacts, and
is rated 8A @ 120-240 VAC or 5A @ 24 VDC (dry
contacts require external power connection). The
relay is de-energized in the normal state (continuity
between C and NC), unless Failsafe is selected from
the menu. It will transition to the alarm state upon
sensor alarm. The alarm relay has a green status
LED to show the state of the relay. The green status
LED indicates when the relay is energized.
Stand-Alone and Feed-Through
Applications
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.
Stand-Alone wiring specifications:
• Cable recommendations: 18/3 shielded cable
(General Cable #C2535A or equivalent).
• Cable should not exceed 1,000 feet total length
from the sensor to the power supply.
Feed-through wiring specifications:
• Maximum input impedance: 700 Ohms.
• Cable recommendations: 18/3 shielded cable
(General Cable #C2535A or equivalent).
• Cable should not exceed 1,000 feet total length
from the sensor to the power supply.