193X704ABG01 GE Industrial Solutions Sensitive Relay Card

The ABB / GE Industrial Solutions 193X704xx Sensitive Relay Card is a universal card used to detect the level of an input voltage, or the difference between input voltages. The relay card can contain one or two sensitive relays. This allows the function to act as a differential relay with the two-relay version, or, with the different connections to the card receptacle, to act in a polarized or non-polarized fashion.

The function is applied in either open -or closed- loop circuits. In many applications the card is employed to switch a signal or pick up another relay whenever it is actuated. In other cases it is the forward gain element in a closed-loop system. In this general area of application, whenever the relay operates it actuates some circuit that directly affects at least one of the inputs to the sensitive relay card. An example of this would be a motor-operated rheostat position control.

The voltage sensitive relay card contains, in addition to the relay(s), a universal amplifier component to allow for wide variation in input voltages. There is a gain adjustment around the universal amplifier which is used to set the sensitivity of the relay action. A bias adjustment is also included to set the level at which the relay(s) will pick up or to act as a zero adjust.

The relay card also contains two limit adjustments. These adjustments are normally left in the fully clockwise or counterclockwise position. In the clockwise position, they serve to limit the universal amplifier output to approximately 10 volts. In the counterclockwise position, they clamp the universal amplifier output at near zero volts. By turning one fully clockwise and the other fully counterclockwise, the relay card becomes polarized. The relay operates on one net polarity of input only.