One 680 system can be installed in an 1800 1+0 clique base or expansion cabinet.
- Base cabinet installation for a 1800 1+0 clique system is located in U-spaces 15-17. U-space 14 must be left empty when a 680 system is installed above it.
- Expansion cabinet installation for a 1800 1+0 clique system is in U-spaces 17-19. U-space 16 must be left empty when a 680 system is installed above it.