Siemens OP121 Installation Instructions

Installation Instructions
Models OP121/OH121
Photoelectric Smoke Detector
Photo Smoke/Thermal Detector
UL268 7th edition listed
These instructions are written in accordance with the
installation guidelines of NFPA 72, National Fire Alarm
Code, and CAN/ULC-S524, The Installation of Fire Alarm
Systems.
DO NOT install this detection device until all
construction is completed.
DO NOT store this detection device where it can be
contaminated by dirt, dust, or humidity.
DETECTOR PLACEMENT
For a clean air application, use 30-foot center spacing
(900 sq ft) from NFPA Standard 72 initiating devices
chapter and CAN/ULC-S524 as a starting point for a
detector installation layout. This spacing, however, is
based on ideal conditions – smooth ceiling, no air
movement, and no physical obstructions. In some
applications, considerably less area is protected
adequately by each smoke detector. In all installations,
place the detector on the ceiling, a minimum of 6 inches
from a side wall, or on a wall, 12 inches from the ceiling.
Follow the drawings provided or approved by Siemens
Industry, Inc. or by its authorized distributors. See
NFPA 72, National Fire Alarm Code, initiating devices
chapter for additional guidance on special issues such
as beamed construction and high stockpiling.
TO AVOID NUISANCE ALARMS
Do not locate the detectors where excessive smoke
concentrations exist under normal conditions, or in areas
of prolonged high relative humidity where condensation
occurs.
Do not locate the detectors next to an oil burner, or
garage where exhaust fumes can trigger an alarm. Other
causes of false alarms are dust accumulation, heavy
concentrations of steam, heavy pipe or cigar smoke, and
certain aerosol sprays.
A6V10281367_d_en_--
2021-12-17
Figure 1
OP121
Photoelectric Smoke Detector
AIR CURRENTS
Before a detector can sense a fire, the products of
combustion or smoke must travel from the fire to the
detector. This travel is especially influenced by air
currents; therefore, consider air movement when
designing the system. While combustion products tend
to rise, drafts from hallways, air diffusers, fans, etc., may
help or hinder the travel of combustion products to the
detector. When positioning a detector at a particular
location, give consideration to windows and doors, both
open and closed, and to other factors influencing air
movement. Do not install a detector in the air stream of
a room air supply diffuser. It is better to position a
detector closer to an air return.
SPECIFICATIONS
Environmental
Operating Temperature:
32 °F (0 °C) to 100 °F (38
Humidity: Up to 95 % RH, non-condensing
Air Pressure: No effect
Air Velocity:

Open area protection:

Duct application:
Alarm Temperature (model OH121): 135 °F (57 °C)
UL listed with STI Mechanical Protection Guard Model:
STI-9604 (see www.sti-usa.com for details)
Electrical
Voltage:
Ripple:
Supervisory Current:
Alarm Current:
Start-up Time:
Figure 2
OH121
Photo Smoke/Thermal Detector
°
C)
0 - 300 ft/min
300 - 4000 ft/min
16-27 VDC
3 V peak-to-peak
100 μA max
30-50 mA
30 seconds max
SIEMENS Industry, Inc.
Smart Infrastructure