Haydon HAY-DC-M Inline DC Volt & Amp Meter, 5–35 V, 7 A, 2.1 mm

Introduction: What the Haydon HAY-DC-M Is and Why It Matters

The Haydon HAY-DC-M Inline DC Volt & Amp Meter is a small, purpose-built test tool for installers, technicians and engineers who work with low-voltage DC systems—most commonly CCTV camera installations. It sits inline between a DC power source and the device under test using a standard 2.1 mm DC plug and socket and simultaneously displays voltage and current readings. With a measuring range of 5–35 V and up to 7 A of current, ±1% accuracy and a compact footprint, the HAY-DC-M is designed to speed up field commissioning and troubleshooting while remaining affordable and rugged enough for repeated site use.

Key Features at a Glance

• Voltage range:5–35 V DC — covers virtually all CCTV camera power supplies and many other DC devices.
• Current range:0.01–7.00 A — captures both inrush and steady-state draw up to 7 A.
• Accuracy:±1% for both voltage and current — dependable for field checks and quick diagnostics.
• Low internal draw:<25 mA — minimal impact on the circuit under test.
• Interface:2.1 mm DC plug & socket — plug‑and‑play between power supply and device.
• Size & weight:85 × 41 × 22.3 mm; 50 g — lightweight and pocketable.
• Warranty:3 years — manufacturer backing for confidence in reliability.

Detailed Specifications and Practical Benefits

• Input voltage:5–35 V DC — this wide range ensures compatibility with most camera power rails and many auxiliary DC devices used on site.
• Input current:0.01–7.00 A — sensitive enough to measure low standby currents and robust enough to show momentary inrush peaks from IR heaters and PTZ mechanisms.
• Accuracy:±1% (voltage & current) — accurate enough for troubleshooting voltage drops on long runs and for verifying that a power supply is delivering within tolerance.
• Power draw:<25 mA — the meter itself draws very little power so it won’t significantly skew measurements on low-current devices.

• Compact form factor:At 85 × 41 × 22.3 mm and 50 g, the HAY-DC-M slips into a kit bag or pocket and is easy to carry across multiple sites during a day of installations.
• Plug & play connection:The 2.1 mm DC plug and socket make it simple to insert the meter inline without wiring or special adapters in most CCTV setups.
• Durability & warranty:A three-year manufacturer warranty gives installers peace of mind for a device that will be handled and used frequently in the field.

• Use for low-voltage DC circuits only. Always isolate and follow standard safe working practices when connecting/disconnecting power.
• Manufacturer datasheet: https://cdn.dynamictech.uk/uploads/datasheets/hay-dc-mdatasheet.pdf
• Manufacturer product page: https://haydonmarketing.com/connectivity-/258-hay-dc-m.html

Use Cases and Scenarios Where the HAY-DC-M Excels

The HAY-DC-M is purpose-built for on-site testing of CCTV and similar low-voltage DC systems. Typical use cases include:

• Commissioning new camera installs:Quickly verify the voltage at the camera and check the initial current draw. This helps confirm correct wiring polarity, verify power supply capacity and identify marginal runs before finalising cable routing.
• Troubleshooting intermittent faults:Use the meter to observe voltage drops caused by poor connections, faulty power supplies or high resistance in long cable runs. The simultaneous display of voltage and current makes it easy to see whether a camera is being starved of voltage while drawing excessive current.
• Measuring inrush currents:Many cameras exhibit brief inrush when IR illuminators or heaters switch on. The HAY-DC-M’s 0.01–7 A range captures these peaks so you can check that your supply and cabling handle transient loads.
• Field verification for maintenance:During routine service visits, the meter provides a rapid pass/fail check on camera power without needing to break into cabinet wiring or remove covers.
• Testing small DC devices:Beyond CCTV, any low-voltage DC device powered with a 2.1 mm connector (recorders, small controllers, sensors) can be checked quickly using this inline meter.

How It Compares to Other Testing Tools

When selecting a test tool for CCTV power checks, technicians often consider multimeters, clamp meters and inline DC meters. Here’s how the HAY-DC-M fits into that landscape:

• Versus handheld multimeters:A multimeter is versatile but often requires leads, setup and can be slower to use in tight spaces. The HAY-DC-M is plug‑and‑play—faster for routine camera checks—and displays both V and A simultaneously, whereas many multimeters show one reading at a time or require reconfiguration to measure current.
• Versus clamp meters:Clamp meters are great for AC current measurement and larger DC currents with specialized clamps, but they aren’t convenient for measuring low DC voltages at a camera connector. The HAY-DC-M offers direct inline measurement specifically suited to CCTV connectors and low-voltage DC ranges.
• Versus other inline DC meters:There are other inline meters on the market, some offering additional features (backlit displays, data logging, higher current ranges). The HAY-DC-M stands out for its balance of range (5–35 V, 0.01–7 A), ±1% accuracy and compact design at a competitive price point—making it ideal for installers who need reliable daily-use performance rather than advanced lab features.

Pricing, Value and Practical Considerations

Suggested retail price: 25.99 (currency to be confirmed). Cost price on record: 21.60. At that suggested price the product provides a simple, low-cost test tool with a gross margin above 16% (currency and tax considerations pending). For most installers and small contractors, the HAY-DC-M represents strong value: it reduces troubleshooting time, avoids needless returns or site revisits and removes guesswork from power-related camera faults.

Customer Feedback and Typical Reviews

Specific customer testimonials for this exact unit are not supplied here, but feedback from installers using inline DC volt/amp meters commonly highlights these consistent themes:

• "Saves time on site" — installers appreciate the plug-and-play convenience and simultaneous V/A readout for fast decisions.
• "Small but robust" — the compact size and modest weight make it a practical pocket tool that withstands daily use.
• "Accurate enough for field work" — ±1% accuracy meets the needs of commissioning and troubleshooting without the cost or complexity of lab instruments.
• "Good warranty support" — a three-year warranty provides confidence for frequent use in professional settings.

If you would like, we can gather and present verified customer reviews or anonymised installer quotes from sales channels once available.

Conclusion: Who Should Choose the HAY-DC-M?

The Haydon HAY-DC-M Inline DC Volt & Amp Meter is an effective, practical tool for CCTV installers, electricians and service technicians who need quick, accurate voltage and current checks on low-voltage DC devices. Its combination of useful voltage and current range, ±1% accuracy, low self-draw and plug‑and‑play 2.1 mm interface make it especially well-suited for field commissioning and troubleshooting. It’s not a substitute for high-end lab equipment or advanced data-loggers, but for everyday site work—verifying power at cameras, spotting voltage drops, observing inrush currents and reducing re-visits—it delivers measurable time savings and confidence.

Safety reminder:Use the HAY-DC-M on low-voltage DC circuits only. Isolate power and follow standard safe working practices when connecting or disconnecting the meter. For complete safety and installation instructions consult the manufacturer datasheet at: https://cdn.dynamictech.uk/uploads/datasheets/hay-dc-mdatasheet.pdf

If you would like a retailer-ready product summary, pricing tiers (including VAT options), or a printable one-page spec sheet for technicians, tell me your preferred currency and primary market (UK/EU/US) and I will prepare those details and a margin analysis.