Maple Systems Silver HMI504T, Installation And Operation Manual

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Power Sup ply Se lec tion
The power supply used to power the OIT should provide an output of +24 VDC 5% measured at the OIT power
terminal block. A 24VDC regulated power supply dedicated to the OIT is required. Refer to the installation guide
that accopanies each OIT for input current requirements.
The power cable for the OIT should be 18AWG, 2-conductor wire with a shield drain wire and protective shield
(foil or braid). The shield drain wire must be connected to earth ground at both ends of the cable. Please refer to the
“Connect the OIT to Power” section for more information.
A power line filter installed at the AC input to the OIT power supply is highly recommended as a safeguard against
conducted RF noise, which is often present on factory power lines. The wires connecting the output of the power
line filter to the power supply should be kept as short as possible to minimize any additional noise pickup. The case
of the power line filter should be connected to a quiet earth ground. The power line filter should have a current
rating of at least 3 Amps with common mode and differential mode attenuation.
Do not use the power supply used to provide power to the OIT to power switching relays, solenoids, or other active
devices.
Ca ble Routing and Noise Im mu nity
Follow these guidelines when routing cable to the OIT:
· Always route the OIT communication cable and the power cable away from any AC voltage or rapidly
switching DC control lines.
· Never bundle the OIT cables together with 120VAC power wires or with relay wiring.
· Try to keep at least 8 inches (20 cm) of separation between the OIT cables and other power wiring. If
voltages greater than 120VAC are used in the system, greater separation is required.
· If the OIT cables must come near AC wiring, make sure they cross at 90 degrees.
· Run AC power wires in a separate grounded conduit to reduce electrical noise interference.
· Keep the cable lengths for the OIT as short as possible. Do not coil excess cable and place it next to AC
powered equipment.
· Cover any equipment used in the enclosure that operates at high frequency or high current levels with a
grounded metal shield.
1010-1001a, Rev 02
10 Sil ver Se ries In stal la tion & Op er a tion Man ual
AC
AC
GND
N
L
White
Black
N
L
G
AC
Line Filter
Green
White to
110Vac neutral
Black to
110Vac load (hot)
To earth
ground
"Quiet”
ground
Bus bar
Power
Supply
Keep short
Power Line Fil ter Connection