Micom P634 - Protective and Operational Grounding

5.5 Protective and Operational Grounding
The device must be reliably grounded to meet protective equipment grounding
requirements. The surface-mounted case is grounded using the bolt and nut,
appropriately marked, as the ground connection. The flush-mounted case must
be grounded in the area of the rear sidepieces at the location provided.
The bracket is marked with the protective ground symbol:
The cross-section of the ground conductor must conform to applicable national
standards. A minimum cross section of 2.5 mm² (≤ AWG12) is required.
In addition, a protective ground connection at the terminal contact on the power
supply module (identified by the letters “PE” on the terminal connection
diagram) is also required for proper operation of the device. The cross-section of
this ground conductor must also conform to applicable national standards. A
minimum cross section of 1.5 mm² (US: AWG14 or thicker) is required.
If a detachable HMI is installed, a further protective conductor (ground/earth) of
at least 1.5 mm² (US: AWG14 or thicker) must be connected to the DHMI
protective conductor terminal to link the DHMI and the main relay case; these
must be located within the same substation.
All grounding connections must be low-inductance, i.e. it must be kept as short
as possible.
19Y5220B
1
2
3
4
1
2
3
4
PE terminal
Description
Nut M4
Bolt M4
Clamp bracket
Tooth lock wash.A4.3
surface-mount. case
PE terminal
Description
Nut M4
Bolt M4
Clamp bracket
Tooth lock wash.A4.3
flush-mount. case
Pos.
1
2
3
4
Pos.
1
2
3
4
Fig. 5-8: Installing the protective grounding conductor terminal.
The protective conductor (earth) must always be connected to the protective
grounding conductor terminal in order to guarantee the safety given by this set-
up.
P634
5 Installation and Connection
5-12 P634/EN M/R-42-A // P634‑311‑653