The GX6315 consists of three groups: A, B and C. Each group has 15 high-current relays, three open collector relay drivers and a connector as shown in the figure below:
GX6315 Architecture
The GX6315 has 45 Form C SPDT relays (see the figure below):
A Typical GX6315 Relay
When the relay is activated, the Change Over (CO) terminal is connected to the Normally Open (NO) terminal. When the relay is deactivated, the CO terminal is connected to the Normally Closed (NC) terminal. After the board is reset, all relays are deactivated.
Different relays are used with version A and B of the board:
● 1 Form A 1 Form B, 7.5A relay is used with version A. Two different parts per relay package, one normally closed the other normally open. Both switch upon activation, normally open closes and normally closed opens.
● 1 Form C, 7.0A relay is used with version B. The relay has one part per package that is connected to normally closed contact and upon activation switches to the normally open.
Note: The single contact ensures a break before make when switching. This prevents potential momentary short circuit between NO and NC.
The GX6315 has nine open collector drivers as shown in the figure below:
A Typical GX6315 Open Collector Driver
Each open collector driver has a diode connected to a group fly-back signal which is available at the connector. All three drivers of a group are connected via three diodes to the same fly-back signal. The fly-back signal can be connected to the external relays supply, thus providing suppression for voltage spikes generated by the relays' coil.