DOLD delay modules for controlled stop category 1 shutdown of drives

DOLD delay modules give drives a controlled shutdown instead of an abrupt one, lowering the risk of injury. They are commonly used on high-speed tools that keep turning after being switched off. During the switch-off delay, motor braking functions can be applied or drive speed regulated, which speeds up the emergency stop of the hazardous motion in line with stop category 1. The machine can be restarted straight away, so productivity does not suffer. A digital time stage keeps the delay setting stable over the long term.

Release-delayed modules make up most of the range. The 45 mm BA 7924 runs without auxiliary voltage, with fixed or adjustable delays up to 30 s and optional redundant or dual timing circuits, rated Cat. 3 / PL d. The BG 7926 also needs no auxiliary supply, uses fixed delays of 1, 2 or 3 s and provides 5 NO or 4 NO / 1 NC outputs. BG 7925 (22.5 mm) and BH 7925 (45 mm) use auxiliary voltage, with 1 NC / 1 NO or 1 NC / 3 NO forcibly guided outputs; BH 7925 is the dual-voltage type.

The 22.5 mm LG 7927 (on-delayed) and LG 7928 (release-delayed) are rated Cat. 3 / PL d and SIL 2. Cross fault detection can be switched on or off, and outputs are 3 NO + 1 NC or 4 NO, each plus a forcibly guided feedback contact.

• Controlled shutdown to stop category 1
• Allows braking or speed control during the delay
• BA 7924 and BG 7926 need no auxiliary voltage
• BA 7924 delays up to 30 s, Cat. 3 / PL d
• LG 7927 on-delayed, LG 7928 release-delayed
• Digital time stage for long-term stability