Belden Grass Valley Kayenne K-Frame, Инструкция по установке и обслуживанию

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102 KAYENNE K-FRAME — Installation & Service Manual
Section 4 — System Cabling
Video Processor Frame GPI/Relay Tally Interface
The GPI (General Purpose Interface) and relay tally interface provides a
means to transfer commands to and from the switcher to external devices.
A one wire per function parallel hardware relay mechanism is used. The
nominal contact rating specification for each relay is 1A, 60 V.
GPI and Relay Tally Connections
Each K-Frame Video Input module has a 50 pin female sub-miniature D
connector on the rear of the chassis, available for GPI and relay tally. Each
connector has 8 GPI Inputs, 8 GPI Outputs and 24 Relay Tally Outputs.
Relays are in groups of four with a common ground. The output relays are
the same hardware but the GPI is being driven by the GPI output software
and the relay tally is driven by the Relay Tally system software. Relay tally
connections can be used to trigger GPIs on external devices.
GPI Inputs
The purpose of the GPI In pins is to provide a stimulus from the external
devices to the switcher. A simple connection of two pins activates the cor-
responding input. An external relay contact or an open-collector output can
be employed.
CAUTION When connecting to an open-collector output, there is no ground potential
isolation between the Video Processor Frame and controlling devices.
Since the circuit ground is led out of the device, cabling should be shielded
for this kind of control. Non-shielded cables may cause EMC and/or ESD
problems. To activate a GPI In you must provide switch closure between a
particular GPI In pin and its common (1 or 34). Pins 1 and 34 of each con-
nector is connected to ground (
Figure 73 ). For applications that span across
more than one connector, only one ground (common) connection is
required.
The following diagram has the GPI inputs on the left.