Napco BDH Battery Diode Harness

Keep critical intrusion and fire systems powered through AC brownouts with the Napco BDH Battery Diode Harness. This Napco Security Technologies accessory provides automatic diode bypass to deliver reliable battery output when AC voltage drops or fails—protecting surveillance, alarm monitoring, and other security devices from service interruptions. The BDH connects the AUX relay to the on-board PS3000 connector and works with the MA3000 battery charging circuit to enable diode bypass only during brownout or no-AC conditions, then automatically restores normal charging when power returns. For correct operation, program "Enable Brownout Limits on AC Fail" and reserve the AUX output for this function. Designed for commercial fire and burglary installations, the BDH simplifies integration with existing Napco systems and reduces the need for a full PS3000 Power Supply Module when only brownout supervision is required. Durable construction and a compact footprint make it ideal for rack or cabinet installations in security control rooms and monitoring centers. Add the Napco BDH to your system to reinforce battery backup and maintain continuous protection—order or consult your Napco distributor for installation guidance.

• Ensures uninterrupted battery backup during AC brownouts by automatically bypassing the charging diode when needed
• Integrates seamlessly with MA3000/PS3000-equipped systems to provide brownout supervision for commercial intrusion and fire applications
• Simple installation connects AUX relay to the on-board PS3000 connector, reducing installation time and complexity
• Automatic restore: bypass is removed when AC power returns, protecting the charging circuit and extending battery life
• Compact, durable harness designed for reliable operation in security, surveillance, and monitoring environments