Maple Systems HMI5000L Series - Manual (Page 7)

HMI5000L Installation Guide 7
1010-1018 Rev 01 www.maplesystems.com
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 door using
a heavy-gauge short braided cable or ground wire to minimize resistance.
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,” which you can find in the Tech Notes section on our web site.
Connect HMI Chassis Ground to Control Panel
To reduce the possibility of electrical interference, connect the chassis
ground terminal of the HMI to a clean earth ground. If the control panel
is metal, make sure it is properly grounded. Then connect a short heavy-
gauge wire (#14 AWG) from the chassis ground terminal of the HMI to a
mounting bolt on the control panel door. The mounting bolt must have
good electrical contact to the control panel; scrape away any paint that
may be covering the panel to provide a good connection.