Brand: Busch
Category: Smart Home
Document Type: Installation Guide
Language: EN
Installation Guide for Professional/Alarmtech
Uploaded: April 20, 2026, 7:44 p.m.
A passive infrared movement detector registers heat sources and switches on connected lighting. When the surveillance zone is vacated, lighting switches off after a delay. It detects invisible infrared heat radiation and activates a pulse when energy patterns change due to movement. The Busch Watchdog is a receiver only. It compensates for ambient range fluctuations due to weather conditions. Detection through obstacles is not possible. Settings for sensitivity, operating modes, time, and dusk levels are externally adjustable. Some models offer comfort and vacation modes, or can be controlled via a remote.
Troubleshooting and error codes
| Light does not come on | - Connect supply voltage, check mains voltage - Lens obscured; clean lens or remove masking strip - No detection; adjust detection zone - Too bright; readjust dusk sensor - Change defective lamp |
| Light is always on | - Device bypassed with switch or similar; switch off - Heat source in the detection zone; realign the Watchdog or cover with masking strip - Device is in Continuous Light mode; operate the break switch in the power supply of the Busch Watchdog |
| Automatic undesired switching | - Switch-on after power failure; wait - Sunlight or heat reflection; readjust area detection or use shutter - Sudden temperature change (storm, rain, snow, fans, etc.) in the surveillance zone; Readjust surveillance zone or select more protected mounting location - Animals in the detection zone |
| Light continuously switches on and off by itself | - Voltage pulse from activated transformers, relays, contactors without overvoltage filters; connect RC element in parallel to the connected load - Distance to the activated light too small; increase distance or cover angle of incidence with masking strip |
| Watchdog does not respond to changes at the dusk sensor | - Watchdog is operating in dazzleproof mode; normal |