Top Terminal – What is it in Vaping?

Definition

A Top Terminal is the uppermost electrical contact on a vapetank or rebuildable atomiser that connects the positive pin of the coil to the battery or mod. Positioned directly above the coil assembly, the top terminal ensures current flows through the atomiser, heating the coil and turning e-liquid into vapour. Unlike bottom-fed terminals, this design keeps the power path high inside the tank, reducing leaking and simplifying maintenance. For Australian vapers, recognising a top terminal helps when swapping coils, cleaning a top-fill system, or matching tanks to mods.

Technical Details

Top terminals are usually machined from gold-, silver-, or nickel-plated brass or stainless steel to maximise conductivity and resist corrosion. They typically measure 2–4 mm in diameter and protrude 0.5–1 mm above the chimneydeck, compressing against the coil’s positive leg when the tank is assembled. Spring-loaded or floating designs maintain constant pressure, preventing resistance jumps that can upset Temperature Control (TC). Variants include hollow terminals for Juice Flow”>juice flow (common in RDTAs), insulated peek sleeves to avoid shorting, and hybrid-safe 510 tops that guarantee battery clearance. Some high-wattage sub-ohm tanks add extra surface area to handle currents above 40 A without overheating.

Usage & Tips

• When changing coils, wipe the top terminal with a dry tissue to remove e-liquid and carbon; build-up here is a leading cause of “No Atomiser” errors.
• Ensure the coil’s positive leg is fully seated against the terminal—an uneven press can mute throat hit or produce a metallic taste.
• Never overtighten tanks onto mods; excessive torque can depress the terminal too far, collapsing internal insulators and creating a hard short.
• If using Titanium Wire in TC mode, confirm the terminal is TC-compatible; mixed-metal contacts can throw off resistance readings.

History & Context

Top terminals gained popularity after 2015 when top-fill tanks became the industry norm. Keeping the electrical contact high allowed manufacturers to seal the base, virtually eliminating the leaking issues that plagued early bottom-coil clearomisers. Today, virtually every mainstream Australian tank—whether MTL or cloud-chasing—uses a top-terminal architecture.