Besam Swingmaster® 900 Series Low Energy Power Operator Meets Hospital's Requirements

I was invited to the installation of Besam Swingmaster 900 Series Power Operators onto double low energy application doors for a positive air pressure unit within a large medical facility. This pair of doors is the secondary set to ensure only purified air is in the unit. Swingmaster 900 units are replacing older power operators that were installed onto the interior side of the doors in the early 1990s.

For this installation, the Auto Door Operator was set to comply with low energy classifications. What qualifies low energy are three components: speed, resistance and “Knowing Act” devices. An automatic door operator can be adjusted to low energy specifications when:

• The door operator must be activated with a ‘Knowing Act’ device, these include push-plates, keypads, card readers and key switches, as well as ‘push and go’ function from the door operator.
• The doors must be calibrated to move and hold open according to the speeds and times defined by ANSI/BHMA A156.19.
• The doors must be calibrated to the open and close torque defined by ANSI/BHMA A156.19.
• All appropriate signage should be installed on the doors as defined by ANSI/BHMA A156.19.

Because this is a hospital, the safety of the patients and their families is of primary importance. Although a low energy power operator does not require presence sensor, presences sensors were included on both the swing side and the interior side of the doors. The presence sensors will detect gurneys, patients who are slow moving and those who stop in the sensing fields.

Note: To maintain low energy classification, these sensors could only inhibit activation or reactivate the doors. Initial activation must be made at a ‘knowing act’ device.

The Swingmaster 900 uses a gear reduction mechanism to open the door. When the door has been opened, the motor holds the open position for the programmed time. Once the time delay expires, closing the door is accomplished by a rack and pinion coil spring mechanism using the motor to provide the brake. Spring force keeps the door closed. Should power be lost, the door will close automatically.

The double outswing doors are equipped with surface-mounted continuous hinges, felt meeting astragal on the swing side of the doors and electric latch retraction concealed vertical rod exit devices on the active and inactive doors. Surface door loops are installed onto the interior side of each door at the height of the exit devices. The active door is equipped with locking exterior trim. Two hardwired, square pushplates are mounted onto the exterior and interior sides of the door.

Mounted onto both doors near the top of on the interior side are BEA SuperScan low energy presence detectors. The SuperScans utilize triangulation technology to detect a presence in the sensing field when the doors are in motion. The SuperScan sensors have a detection range of up to 12 feet.

An Overhead Presence Detector (OPD) is mounted above the door on the swing side. A BEA Bodyguard presence sensor is located on the center of the 88” wide doorframe header. The Bodyguard is designed for swing side operation of the door and has two settings, one for the open door and the second for the closed door. The open door setting can detect through the door threshold 12” to 18”. The Bodyguard III will either keep the doors in the open or closed position, or will prevent the closed door from opening if a presence is detected. There are fixed and customizable sensing patterns.

When activated, the two push plates send a signal to the door operator to open the door. This is a “Knowing Act,” where someone consciously initiates the opening of the low energy door.

A second pair of doors is located approximately 25 feet along the corridor between this set of doors and the unit. Between the two pairs of doors are offices, but no other corridors. This alleviated some of the demands on the installation, as the opening where the power operator was being replaced did not have to keep the doors closed in order to maintain the positive pressure within the unit.