Woodward highprotec MRI4, User Manual

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Installation and Connection
Installation Diagram 8-Pushbutton Version
Even when the auxiliary voltage is switched-off, unsafe voltages might remain
at the device connections.
The installation diagram shown in this section is exclusively valid for devices
with 8 pushbuttons at the front side of the HMI.
(INFO-, C-, OK-, CTRL-Pushbutton and 4 Softkeys (Pushbuttons)).
B1 Housing Door Cut-out (8-Pushbutton Version). (All dimensions in mm, except dimensions in brackets [inch].)
The housing must be carefully grounded. Connect a ground cable
(protective earth, 4 to 6 mm
2
[AWG 11‒9], tightening torque 1.7 Nm
[15
lb⋅in
]) to the housing, using the screw that is marked with the ground
symbol (at the rear side of the device).
Moreover, the power supply card needs a separate ground connection
(functional earth, min. 2.5 mm
2
[≤ AWG 13], tightening torque 0,56 ‒
0,79 Nm [5‒7
lb⋅in
]). See the “Terminal Marking” diagram in Section “DI-4
X – Power Supply and Digital Inputs” to check for the correct terminal.
All grounding connections (i. e. protective and functional earth) must be
low-inductance, i. e. as short as possible, and national standards – if
applicable – must be followed.
Be careful. Do not overtighten the mountings nuts of the relay
(M4 metric 4 mm). Check the torque by means of a torque wrench (1,7 Nm [15
lb∙in]). Overtightening the mounting nuts could due to personal injury or
damage the relay.
30 MRI4 DOK-HB-MRI4-2E