Wall Pack Efficiency: Photocells vs. Motion Sensors Explained

We’ve all at one point walked outside in the dark, without exterior lights illuminating above us. It can be a discomforting experience, especially if in a place we’ve never been before. Sometimes we doubt where we’re actually heading when it’s dark out, even though we’ve been on the same path so many times during the day and the GPS is in fact pointing us in the right direction. We notice the difference between what’s at night versus during the day, and we doubt our familiarity with the surroundings; it’s one of the main reasons why hiking is dangerous after the sunsets: we lose sense of our surroundings when we doubt the change in scenery. Even in developed areas it’s very easy to get lost whether we could not be in the right state of mind or simply distracted by devices or technology. 

In the world of outdoor lighting, wall packs and photocells are crucial components that serve both functional and safety purposes. Wall packs are a type of outdoor lighting fixture typically mounted on the exterior walls of buildings, providing illumination for safety, security, and aesthetic purposes.

Wall packs are commonly used in commercial, industrial, and residential settings to ensure that areas such as parking lots, pathways, and building exteriors are well-lit during nighttime. While wall packs have the responsibility to provide bright and consistent illumination, enhancing visibility and security, they are also designed with energy-saving in mind. Today, we will go over the two common methods outdoor lighting fixtures use to save on energy and the different applications they are used to serve. 

The Role of Photocells in Wall Packs

Photocells, also known as photoelectric sensors, are devices that detect light levels. When paired with wall packs, photocells automatically turn the lights on at dusk and off at dawn. This automation provides several benefits:

Energy Efficiency: Lights operate only when needed, reducing energy consumption.

Convenience: Automatic operation eliminates the need for manual intervention.

Consistency: Ensures that the lighting schedule is maintained consistently, enhancing security.


Photocells are often paired with wall packs to ensure that the lights operate only when needed, thus conserving energy. The photocell detects the ambient light levels and switches the wall pack on at dusk and off at dawn, ensuring that the lights are only active during low-light conditions.

Why Motion Sensors are Not Ideal for Wall Packs

While motion sensors are effective for many lighting applications, they are not typically used with wall packs for several reasons:

Coverage Area: Wall packs are designed to illuminate large areas consistently. Motion sensors, on the other hand, are best suited for smaller, targeted areas where brief illumination is required.

Safety Concerns: Consistent lighting is crucial for safety in commercial and industrial settings. Intermittent lighting from motion sensors could create dark spots, potentially increasing the risk of accidents or security breaches.

Frequent Activation: In high-traffic areas, motion sensors would cause the lights to turn on and off frequently. This not only reduces the lifespan of the bulbs but can also be distracting and annoying for occupants and passersby.

Maintenance Issues: Motion sensors can be more prone to false activations due to environmental factors like wind, rain, or the presence of animals. This can lead to increased maintenance and operational costs.

Although motion sensors are the most ideal solution for optimal energy efficiency and cost-saving, security lights like the wall pack or lighting fixtures that need to be on during the night require photocell technology instead of motion sensors simply because of safety concerns and preventing misfortunes. The distress of the motion sensors on wall packs flickering on and off constantly would also destroy the purpose of wall packs. With wall packs designed being dark sky compliant in mind, users can be at ease that wall packs not only benefit the environment but also enhance the quality of life by promoting a more natural and less intrusive night-time atmosphere.

back of wall pack with photocell
back of wall pack with photocell on the right
Side of wall pack with photocell
side of wall pack with photocell