Pharmaceutical, Cleanroom Sterilization Master-Secondary Countdown Timers
The DC-25T-DN-BCD-EOP is a custom-built Master-Secondary, Manufacturing, Multi-Input Countdown Timer designed specifically for Mechanical Systems Inc. This system provides precise, repeatable countdown control in industrial environments where accuracy, visibility, and durability are critical. Built around our BCD rotary switch configuration, this timer allows operators to quickly preset a countdown duration and control it through clearly labeled push buttons, while simultaneously displaying identical time data on both the master and secondary units.
This order features a true master and secondary configuration connected via a dedicated data line through terminal blocks. Whatever is displayed on the master unit is mirrored in real time on the secondary unit, ensuring synchronized visual feedback across multiple viewing points on the production floor. This redundancy is ideal for manufacturing operations where timing must be visible from different workstations or zones.
At the core of this system is the BCD rotary switch interface located on the master enclosure. Using a flathead screwdriver, operators can easily adjust the preset time by turning the four-position BCD rotary switches. Once the desired time is set, the unit counts down from that preset value when activated through the momentary contact push button switches. These switches are connected internally through an opto base board mounted inside the rear of the master enclosure, providing reliable multi-input functionality and electrical isolation.
Operationally, the timer features three primary control functions:
- Start / Stop button
- Reset button
- Reset and Start button
For example, when preset to 10 seconds, pressing the Start/Stop button initiates a countdown in tenths of a second. When the timer reaches zero, an audible relay click from the master unit indicates the end of the countdown cycle. The Reset button restores the preset time after reaching zero. The Reset and Start function allows operators to immediately restart the full preset countdown with a single press, even if the timer is paused mid-cycle.
Adjusting the countdown duration is straightforward. By inserting a flathead screwdriver into the appropriate BCD rotary switch position, users can modify individual time increments. For instance, switching from 10 seconds to 1 minute is accomplished by adjusting the second rotary switch. After resetting, the display immediately reflects the updated preset time. The system can count down from any preset value up to 99 minutes and 59 seconds, offering flexibility for a wide range of industrial timing applications.
When the countdown reaches zero, the end-of-period relay activates for one second and produces two audible clicks. This relay can handle up to 15 watts and provides a clear signal that the timing cycle has completed.
Typical use cases include:
- Notifying workers when a shift, task, or process cycle is complete
- Controlling immersion times for materials, such as metal submerged in acid
- Managing timed manufacturing processes
- Providing synchronized countdown visibility across multiple stations
From a hardware perspective, both the master and secondary units are built for industrial durability. Each enclosure is constructed from tough 14-gauge aluminum with a black powder-coated finish that resists fingerprints and dust. The four-digit displays measure 2.3 inches and are visible from up to 120 feet away, ensuring clear readability in large facilities.
Key hardware specifications include:
- Four-digit display per unit
- Maximum countdown range: 99 minutes, 59 seconds
- 120–240 VAC power adapter with 6-foot cord
- 4×4 or 2×4 electrical rough-in box slotted teardrop knockouts for mounting
- Master-Secondary data-line connection for redundant display control
- Multi-input functionality through opto base board
- End-of-period relay rated for 1 second at 15 watts
The DC-25T-DN-BCD-EOP provides a reliable, synchronized, and easy-to-configure countdown solution tailored for manufacturing environments. Built for precision and long-term durability, this custom order delivers clear timing control and dependable performance for Mechanical Systems Inc.
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