Part numbers CA2DK122, CA2DK22 and CA3DK22 referred to latching contactor relays in the old contactor relay range, which have now been replaced.
They consisted of two N/C contacts and two N/O contacts and two coils, A and E. When A is pulsed the contactor closes, then a second pulse onto E will open the contactor.
There is no direct substitution, but there is a complementary solution using CAD control relays which involves combining two products; a control relay CAD32xx and a latch block LAD6Kxx
(where xx is the control voltage code)
A pulse on the contactor coil terminals A1 and A2 causes the contactor to close.
Mechanical latching of the LAD6Kxx keeps the contactor closed.
A pulse on the coil of the LAD6Kxx, terminals E1 and E2, opens the contactor.
The duration of the control pulse on the mechanical latch block and the contactor must be:
>= 100 ms for AC control
>= 200 ms for DC control