ADLINK cPCI-7252 - Manual (Page 27)

Installation 17
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 2-4: Connection between PCI-7250 and PCI-7251
Legend
Din: Digital input channel n
IGND: Ground of DIn signals
DinH: Digital input channel n with positive polarity
DinL: Digital input channel n with negative polarity
NC n: Normal close pin of relay n
NO n: Normal open pin of relay n
COM n: Common pin of relay n