AdapterGuru
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How the Engine Works

Adapter Guru executes deterministic electrical engineering formulas directly inside your browser. No black-box algorithms, no cloud telemetry, and zero tracking cookies.

The 6 Sequential Validation Steps

01

Step 1: Voltage Strict Equivalence (ΔV = 0)

V_adapter == V_device

Voltage is the electrical pressure forced across your device circuitry. If the adapter outputs more voltage than requested (Overvoltage), internal linear regulators and capacitors overheat and fail. If it outputs less (Undervoltage), the device will experience brownout loops or boot failure.

Rule: Adapter Volts must match Device Volts (±5% is a standard regulatory margin guideline for many DC devices).
02

Step 2: Amperage Capacity & Headroom (I_adapter ≥ I_device)

I_adapter ≥ I_device

Amps measure current capacity. A device only draws what it requires. Connecting a 12V 5A power supply to a 12V 2A router is safe under normal operating conditions — the router draws 2A and the adapter operates cooler with 60% thermal reserve headroom. An undersized adapter (< 2A) will overheat, drop voltage, and trigger thermal shutdown.

Rule: Adapter Amps can safely be equal to or higher than Device Amps.
03

Step 3: Power Type Uniformity (DC Direct vs AC Alternating)

Power_type(adapter) == Power_type(device)

Direct Current (DC ⎓) maintains steady unidirectional polarity. Alternating Current (AC ~) reverses direction 50/60 times per second. Supplying AC to a DC gadget can severely damage sensitive microcontrollers unless an internal rectifier is present.

Rule: Never connect an AC-output brick to a DC-input device.
04

Step 4: DC Polarity Alignment (Center Positive ⊕ vs Center Negative ⊖)

Polarity(adapter) == Polarity(device)

The vast majority of consumer electronics use Center Positive (⊕), where the internal contact is (+). Audio equipment and Boss guitar pedals commonly use Center Negative (⊖). Connecting reverse polarity causes reverse diode breakdown or rapid component damage.

Rule: Both diagrams on the brick and device must point to the same center terminal.
05

Step 5: Physical Connector Dimensions (OD × ID Mating)

OD_plug == OD_jack && ID_plug == ID_jack

DC barrel connectors are defined by Outer Diameter (OD) and Inner Pin Diameter (ID). The engine specifically evaluates the common 5.5×2.1mm vs 5.5×2.5mm trap: a 2.5mm plug on a 2.1mm socket will physically slip in but will make loose, intermittent contact that causes voltage drop, overheating, or reboots.

Rule: Outer barrel and center pin must mate snugly without wobbling or losing contact.
06

Step 6: Total Wattage Rating & Thermal Load (P = V × I)

P_watts = Volts × Amps

The engine computes total power output in Watts for both ends. It verifies that the power supply possesses at least 100% of the device nominal operating wattage and suggests a 20-25% continuous duty headroom margin (industry recommended 80% load guideline) for 24/7 equipment like routers and security cameras.

Rule: Adapter Wattage must equal or exceed Device operating Wattage.

Electrical Decision Matrix

Summary of the engine's deterministic verdict states and electrical consequences:

ConditionEngine VerdictPhysics ConsequenceSafe to Plug In?
Same Voltage, Equal Amps✓ PASS (Compatible)Nominal 100% electrical load matchingYES
Same Voltage, Higher Amps✓ PASS (Safe Headroom)Device pulls required amps, adapter runs coolerYES
Same Voltage, Lower Amps! WARNING (Overload)Brick overheats, voltage sags, device rebootsRISKY
Higher Voltage (Overvoltage)× HAZARD (Blowout)Excessive current stress, risk of capacitor failureNO
Reversed Polarity (⊕ vs ⊖)× HAZARD (Reverse Bias)Reverses diode polarity, risk of rapid circuit damageNO
AC Adapter on DC Device× HAZARD (Waveform)Alternating current risks damaging DC filtering circuitNO
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Input your specifications and watch the engine evaluate all 6 safety parameters in real time.

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