SNAP D-series racks are designed for discrete control applications and can accommodate 4, 6, 8, or 12 SNAP 4-channel digital modules. These racks use an industry-standard 50-pin header connector, which allows these racks to be used in a variety of applications. The logic side of the I/O circuitry can be controlled directly or by using an Opto 22 PCI-AC5 (PCI bus) or G4AC5 or AC5 (ISA bus) PC adapter card. In addition, the 4-module-position SNAP-D4M can be used with Opto 22s Classic brain boards. These boards use one of Opto 22s industry-standard protocols (mistic, Optomux, or Pamux) to control the I/O and communicate either serially or in parallel. Field devices are wired directly to the top-mounted removable connectors on the SNAP I/O modules. The module and rack design allows modules to simply snap on and off the mounting rack. SNAP racks use a retention-rail locking system that holds modules securely to the rack. Normally, a hold-down screw is not required. However, for applications that require additional mounting security, SNAP racks have provisions for two 4-40 by 1/2" standard machine screws to hold each module in position. All SNAP racks offer panel mounting and the option of DIN-rail mounting. SNAP racks use a single 5 VDC power source. Power requirements: 5 VDC +/- 0.1 VDC at 400mA maximum. Operating temperature range: 0 to 70 degree celsius. Relative humidity: 95 percent, non-condensing. Length: 7.74" Center to center length: 5.53".
Underwriters Laboratory, IEC 950: 1991-09, 89/336/EEC, 2002/95/EC, Defense Federal Acquisition Regulation Supplement