Endress+Hauser RMM621 Bedienungsanleitung Seite 23

Fig. 3: Mounting device on top-hat rail
3.2.1 Installing extension cards
"
Caution!
When using extension cards, venting with an air current of at least 0.5 m/s is necessary.
You can equip the device with various extension cards. A maximum of three slots are available
in the device for this. The slots for the extension cards are marked with B, C and D (→ Fig. 4)
on the device.
1. Make sure that the device is not connected to the power supply when installing and
removing an extension card.
2. Remove the blanking cover from the slot (B, C or D) of the basic unit by pressing together
the catches on the bottom of the device (see Fig. 4, item 2), while at the same time press-
ing in the catch on the rear of the housing (e.g. with a screwdriver) (see Fig. 4, item 1).
Now you can pull the blanking cover up out of the basic unit.
3. Insert the extension card into the basic unit from above. The extension card is not correctly
installed until the catches on the bottom and rear of the device (see Fig. 4, items 1 and 2)
lock into place. Ensure that the input terminals of the extension card are on top and the
connection terminals are pointing to the front, as with the basic unit.
4. The device automatically recognizes the new extension card once the device has been cor-
rectly wired and has been commissioned (see 'Commissioning' Section).
Installation
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