The LAD6K10* / LA6DK20* latch block that attaches to the TeSys D series contactors and control relays enables mechanical latching.

Due to the design of the coil in the latch block, there are a number of precautions to be observed when using these devices. In addition, where the older 'D2' contactors and latch blocks are replaced with the current TeSys D versions, there are some important differences to consider.

Precautions to observe when using the LAD6K10* / LA6DK20* latch block (also refer to the user manual attachment).

• Never energise the contactor / relay coil and the latch block coil at the same time.
• Minimum pulse time required to unlatch the contactor:
  100 ms with ac coil
  250 ms with dc coil
• Maximum pulse time: 10 seconds
• Maximum operating rate: 1200 cycles/hour

Important differences between the original LA6DK1* , LA6KDK2* and LA6DK3* used on the 'D2' series and the current TeSys D series LAD6K10* / LA6DK20*

There are important differences between the new latch block and the original 'D2' type;

• The new latch block does not incorporate an auto cut out of the un-latch coil within the latch block. Thus, it is important to ensure the circuit controlling the energisation of the de-latch coil confirms to the precautions detailed above.
• LA6KDK2* and LA6DK3* were also fitted with a N/C contact that could be used as a 'cut throat' for the coil circuit of the host D2 contactor. This feature is not included on the TeSys D latch blocks.

*Coil code letter.

Please visit our website www.se.com/uk for more information on the latch blocks, mounting and wiring instructions.

Released for:Schneider Electric UK