HMI5000L Installation Guide 7
1010-1018 Rev 12 www.maplesystems.com
Control Panel Grounding
The control panel must be connected to a good, high-integrity earth
ground both for safety considerations and shielding purposes. Maple
Systems cannot overemphasize the importance of good grounding.
Failure to use good grounding procedures during installation may cause
sporadic malfunction of the HMI.
Connect the HMI chassis ground terminal to a reliable earth ground with
a low-resistance path. Refer to Figure 1:
Route all earth ground wires that lead from the HMI, the PLC, the
power supply, and the line filter to a central earth ground point such as a
barrier strip. This will ensure that no ground current from one device
influences the operation of the other devices.
Connect the HMI chassis ground terminal to the control panel using a
heavy-gauge short braided cable (#14 AWG) or ground wire to minimize
resistance. Then, make sure the panel is properly grounded to a clean
earth ground.
Note:
If the control panel is made of a non-conductive material, it is
essential that the chassis ground terminal of the HMI is connected to
a clean earth ground point located close to the panel.
Connect the power cable’s shield wire to the HMI’s chassis ground
terminal.
Connect the control panel to earth ground using a copper grounding
rod close to the HMI and control panel.
Hinged doors on control panels do not provide a long-term electrical
connection to the rest of the enclosure. Corrosion develops over time
and prevents good electrical contact. For this reason, a separate wire
braid should be installed from the hinged control panel to the rest of the
enclosure.
For a more in-depth overview of ground wiring techniques, refer to
Technical Note #1027, “OIT Ground Wiring and Electrical Noise Reduction”
in the Technical Notes section of the Maple Systems website.
Installation
It is necessary to follow all installation procedures described in this
chapter for electrical noise immunity and CE compliance. The Maple
Systems HMI is designed to connect easily to a PLC. External rear
connectors provide quick connections for power, communications and
programming wiring.
Summary of Contents for HMI5000L Series
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