Siemens 500 NIM - Manual (Page 40)

Installation 3-5 SIMATIC TIWAY I Series 500 NIM User Manual
Once the keys are in place, orient the module so that the indicators are on
the top half of the module. Then, carefully push the module into the I/O
base as shown in Figure 3-2. When the module is fully seated in the I/O
base, tabs will hold the module in place. To remove the module, pull the tabs
away from the module and take it out of the I/O base, being careful not to
damage the edgecard.
Figure 3-2 Installing the NIM in the I/O Base