Dahua NVR-NV21A04-P4-S3 4 Channel PoE Network Video Recorder – Compact 1U, 1 HDD, H.265+ & SMD Plus

The Dahua NVR-NV21A04-P4-S3 4 Channel PoE Network Video Recorder is a compact IP security recording solution designed for residential and small business surveillance systems.

Featuring 4 integrated PoE ports, 1 HDD bay, Smart H.265+ video compression, adaptive decoding and AI features supported by compatible cameras, this Dahua NVR provides a convenient foundation for a four-camera IP security system.

Its compact 1U design is suitable for homes, retail stores, offices and commercial properties requiring centralized security recording.

Key Features

• 4-Channel IP Camera Recording: Supports up to four compatible network security cameras.
• 4 Built-In PoE Ports: Provides network and power connectivity for compatible PoE IP cameras.
• 1 HDD Bay: Supports installation of one compatible surveillance hard drive.
• Compact 1U Design: Space-efficient recorder construction.
• Smart H.265+ Compression: Supports efficient video compression for storage and bandwidth management.
• Multiple Video Formats: Smart H.265+, H.265, Smart H.264+ and H.264.
• Adaptive Decoding: Supports adaptive video decoding.
• Maximum Decoding Capability: Up to 6 × 1080p at 30 fps.
• AI Perimeter Protection Support: Supports perimeter protection generated by compatible cameras.
• SMD Plus Support: Supports intelligent motion detection from compatible cameras.
• Third-Party IP Camera Connectivity: Supports compatible third-party network cameras.
• Security Baseline 2.1: Incorporates the specified security baseline.

4-Channel IP Camera Recording

The Dahua NVR-NV21A04-P4-S3 supports up to four compatible IP security cameras.

It provides centralized recording for multiple monitoring locations, including residential entrances, driveways, retail stores and offices.

The maximum supported camera recording resolution was not specified in the supplied product information and should be confirmed before installation.

Four Integrated PoE Ports

The NVR includes four built-in PoE ports designed for connecting compatible IP security cameras.

Power over Ethernet allows supported cameras to receive network connectivity and electrical power through Ethernet cabling.

Benefits include:

• Simplified camera installation
• Reduced need for separate power adapters
• Centralized camera connections
• Convenient setup for four-camera systems

The total PoE power budget and individual port limits should be verified before connecting cameras.

Single HDD Bay for Local Video Storage

The Dahua NVR-NV21A04-P4-S3 features one HDD bay for installing a compatible surveillance hard drive.

Recorded footage can be stored locally according to the installed HDD capacity and recording configuration.

Recording duration depends on:

• Number of cameras
• Video resolution
• Recording frame rate
• Video bitrate
• Compression format
• Recording schedule
• Installed hard drive capacity

Important: The supplier confirms one HDD bay but does not specify whether a hard drive is included.

Smart H.265+ Video Compression

The NVR supports the following video formats:

• Smart H.265+
• H.265
• Smart H.264+
• H.264

These formats help manage video bandwidth and storage requirements.

Smart compression can reduce storage usage when supported by the connected cameras and recording configuration.

Actual storage efficiency depends on video settings and scene activity.

Adaptive Video Decoding

The recorder supports adaptive decoding with a specified maximum decoding capability of 6 × 1080p at 30 fps.

This specification describes the NVR’s decoding capacity and does not increase its four-channel camera limit.

Actual playback and display performance depend on the connected camera streams and system configuration.

AI Perimeter Protection

The Dahua NVR-NV21A04-P4-S3 supports perimeter protection analytics generated by compatible IP cameras.

These intelligent functions can help monitor designated security areas and identify supported intrusion-related events.

The available detection rules depend on the connected camera model and configuration.

SMD Plus Intelligent Motion Detection

SMD Plus is Dahua’s intelligent motion detection technology.

When paired with compatible cameras, it can help identify relevant motion events and improve security alert management.

Important: The supplied specifications state AI by Camera. The connected camera must support the relevant intelligent functions; independent AI processing by the NVR is not confirmed.

Third-Party IP Camera Compatibility

The NVR supports connection to compatible third-party network cameras.

This provides flexibility for installations using different IP camera equipment.

Compatibility and available features vary by camera model, firmware and supported protocols.

Third-party cameras may not support every Dahua-specific AI feature.

Compact 1U Design

The Dahua NVR-NV21A04-P4-S3 features a compact 1U chassis suitable for space-conscious security installations.

It is a practical option for residential and small commercial surveillance systems.

Technical Specifications

Specification	Details
Brand	Dahua
Model	NVR-NV21A04-P4-S3
Product Type	Network Video Recorder
Camera Channels	4
Integrated PoE Ports	4
HDD Bays	1
Form Factor	Compact 1U
Video Formats	Smart H.265+, H.265, Smart H.264+, H.264
Maximum Decoding Capability	6 × 1080p @ 30 fps
Adaptive Decoding	Supported
AI Processing	AI by Compatible Camera
Perimeter Protection	Supported by Compatible Camera
SMD Plus	Supported by Compatible Camera
Third-Party IP Cameras	Supported, Subject to Compatibility
Security Baseline	2.1
Maximum Camera Resolution	Not Specified
Incoming Recording Bandwidth	Not Specified
Maximum HDD Capacity	Not Specified
HDD Included	Not Confirmed
PoE Power Budget	Not Specified
HDMI Output	Not Confirmed
VGA Output	Not Confirmed
Remote Viewing App	Not Confirmed
Dimensions	Not Specified
Weight	Not Specified

Ideal Applications

The Dahua NVR-NV21A04-P4-S3 is suitable for:

• Home security systems
• Retail stores
• Small offices
• Commercial entrances
• Residential driveways
• Restaurants
• Small warehouses
• Four-camera IP surveillance installations

Installation and Compatibility Notes

• Compatible IP cameras are required.
• Confirm camera power requirements against the NVR’s PoE budget.
• Verify supported camera recording resolutions.
• Install a compatible surveillance HDD if one is not included.
• Confirm third-party camera compatibility before installation.
• AI features require compatible cameras.
• Verify remote viewing and video output specifications before purchase.

Buy Dahua 4 Channel PoE NVR in Canada

Shop the Dahua NVR-NV21A04-P4-S3 4 Channel PoE Network Video Recorder at Tech Vision Electronics.

We supply Dahua IP cameras, network video recorders, PoE networking equipment and security system accessories for residential and commercial installations.

Visit our Scarborough store, serving Toronto, Mississauga, Brampton, Markham, Pickering and customers across Canada.

Tech Vision Electronics
1261 Kennedy Road, Unit 4
Scarborough, Ontario M1P 2L4
Phone: 416-551-7334
Website: www.techvisionelectronics.com