APT IMM24 model has been specifically developed to cope with the constantly high amperage draw found with immersion heaters and also the wide variety of device must be connected for B2, T or TS (momentary or timer activation on close) feature. If momentary contact on close (B2) wiring is desired, move. ‧sec : Twin Timer Unit - Min : Sec (APT-9S only) ‧Note this incorrect wiring of this controller can damage it and lead to other hazards.head on the clock face aligns with the correct time The dial shows the 24 hour clock. Note that 9 = Connect wiring according to the wiring diagram. Install in accordance to wiring and current building regulations. Please read the instructions carefully. If in any doubt contact the Timeguard Helpline.