ADLINK LPCI-7250 - Manual (Page 36)

28 Installation
2.7 PCI-7250 and PCI-7251 Connection
There are 8-relay outputs and 8-isolation inputs on both the PCI-
7250 and PCI-7251. The PCI-7251 is used as an expansion for
the PCI-7250. The operations of the PCI-7251 are the same as
that of the PCI-7250. There can be at most 3 PCI-7251 expansion
boards to one PCI-7250. Therefore, the PCI-7250 can control up
to 32 relays and detect 32 input signals.
Figure 2-6: Connection between PCI-7250 and PCI-7251