Pass Box Interlocking System


In the process of material transfer from unclassified area to classified area pass box used. Pass box is rectangular box with two or three doors. The doors are interlocked such a way that doors cannot be open at the same time, due to which pressure losses and bacterial contamination doesn't take place throughout the material transferring process.

The prevention of simultaneous access of doors is been achieved by our Pass Box controller by ensuring that when one door for a Pass box is open then other doors closed.

  • Pass Box Interlocking System


  • Advanced Micro Controller based 2Door or 3Door STATIC/DYNAMIC Passbox interlocking system.
  • Status indications with High intensity RED color BARLED's.
  • Door Status indications like “GO”,”WAIT”, “CLOSE DOOR”,“DOOR OPEN” messages for every pushbutton.
  • Buzzer output for door is kept open more than specified time from 2 to 30 min.
  • Timer value can set by using 3keys keypad
  • Password protection for Timer value setting
  • Timer value can set maximum of 999
  • Timer operates as per user requirement and it is preprogrammed
  • When Door 1 is opened the display on the Door 2 and Door 3 will indicate “WAIT” and at the Door 1 the display will indicate “DOOR OPEN”
  • When any of the Door is kept open beyond a particular time say 2 min, a buzzer will be blown and the display at the doors will indicate “CLOSE DOOR”

UV Lamp Controlling

  • UV Lamp ON for both Doors closed
  • UV Lamp OFF for both Doors Open
  • Manual ON/OFF using passbox interlocking system with LAF/BUF ON and OFF Control DPM

Blower Fan Controlling

  • Blower fan ON when any of door open
  • Blower fan OFF when both doors closed
  • Manual ON/OFF using passbox interlocking system with LAF/BUF ON and OFF Control DPM

CF Lamp Controlling

  • CF Lamp ON when any door is open
  • CF Lamp OFF for both Doors Closed
  • Manual ON/OFF using passbox interlocking system with LAF/BUF ON and OFF Control DPM
  • All Doors are provided with Electromagnetic locks/Electric Strikers
  • 3 digit 0.39” 7-Segment RED display to timer value
  • Soft-touch membrane keypad provided to program timer values
  • 3mm Diffused red LED's for Blower failure Indications
  • Soft-touch membrane & Capacitive Touch keypad provided to program timer values
  • Soft-touch membrane keypad & Capacitive Touch provided to control LAF/BUF controls
  • 5mm Diffused Bi-Color LED indication to display ON/OFF status of LAF/BUF Controls
  • Door delay time: pre programmed as per requirement.

About Us

Styrax Instruments India Pvt. Ltd., has been one of the prominent manufacturers and suppliers of Process Measure and Control Systems.

Clean room Interlocking Systems, Automation Solutions and hi-tech security and access control systems.


STYRAX Instruments India Pvt Ltd.

H.No: 2-77, Near Gajularamaram Chowrastha, Gajularamaram, Hyderabad - 500055. Telangana - INDIA.
Ph: +91 9989222456

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