The card I am having problem with is DO card, 8-Channel, High-Side type. We are trying to use this card's channels to energize the relay NO contact. The card output range is 24 VDC. I suppose 24 VDC for logic 1 and 0 VDC for logic 0. However, we can get 24 VDC for logic 1 and 17 VDC for logic 0, which let us close contact of the relay but not able to open the contact at logic 0 of the program. Has anyone seen this problem before and what can I do about it? Thanks!