Hach SC4500 Manuel D'utilisation Simplifié page 20

Terminal Description
1 Relay 2, NC
2 Relay 2, common
3 Relay 2, NO
NC = normally closed; NO = normally open
4.3.5 Install an expansion module
Explosion hazard. This manual is only for installation of the unit in a non-hazardous location. For
installation of the unit in hazardous locations, use only the instructions and approved control drawing
provided in the hazardous location installation manual.
Expansion modules for analog outputs, analog inputs, analog sensors and Profibus communication
are available for the controller. Refer to the documentation supplied with the expansion module for
additional information.
4.4 Close the cover
Electrocution hazard. High voltage wiring for the controller is connected behind the high voltage
barrier in the controller enclosure. The barrier must remain in place except when installing modules,
or when a qualified installation technician is wiring for power, relays or analog and network cards.
Close the controller cover and make sure that the cover screws are tight to keep the environmental rating of the
enclosure.
After the power connections are made, install the high-voltage barrier. Make sure that the high-
voltage barrier is correctly put on the enclosure guides and fixed to the main PCBA. A click sound is
heard when the high-voltage barrier is correctly installed. Make sure that the lower part of the high-
voltage barrier (soft rubber lip) is correctly installed and has no deformation. Refer to
Close the controller cover. Tighten the cover screws with 2 Nm (17.70 lbf-in) torque. Refer to
Figure 7 on page 15.
20 English
Table 4 Wiring information—relays
W A R N I N G
D A N G E R
N O T I C E
Terminal Description
4 Relay 1, NC
5 Relay 1, common
6 Relay 1, NO
Figure 11.