Bug

Based around a resettable PTC element, the Bug is a high-amp, low voltage-drop short-circuit protection module for 18XXX batteries that adds dependable safety to mechanical mods.

Over-currents and short-circuits are almost unavoidable when working with rebuildable atomizers and mechanical mods. Usually caused by bad atomizer resistor set-ups, shorted wires and wrong connections, sustained over-current conditions always lead to battery overheating and, under extreme conditions, battery and equipment damage. Make-break contacts in mechanical mods are among the first components that may show signs of degradation after a hard short-circuit.

VV/VW mods usually include dedicated over-current protection that acts fast to interrupt current flow if a fault occurs. However, mechanical devices usually score quite low in terms of safety — since they are designed to be simple / rebuildable, they usually come without any protection circuitry at all.

Collapsible springs, which are often used to provide a basic level of short-circuit / overheating safety, are too slow to prevent battery and equipment damage, since they react only after the battery has already overheated. High-drain IMR batteries, which are usually the de-fact standard for use with mech mods, come with no integrated protection circuit boards. This leaves us with very few options for protecting our gear and minimizing the risks of battery and equipment failure.

Resettable polymeric fuses have been around for quite a while – they provide an easy means of secondary over-current protection, which is fast enough to prevent component and battery damage. These fuses do not ‘burn’ like the traditional ones – they use a polymeric element that interrupts the circuit during an over-current condition. The resistance of such an element is dependent on the current and temperature — a short-circuit quickly brings the fuse to a high-resistance state. When the fault is removed, the device cools down fast and reverts back to its low-resistance state.

Since the performance of these modules depends on the operating current and the fuse’s / ambient temperature, proper component selection is key to achieving good performance under non-fault conditions.

The Bug is designed to operate with a voltage drop between 0.05 V (at 2A) and 0.15 V (at 6A). Practically, using it with an atomizer resistance down to 0.8 Ohms will have a very small impact on performance, since the resistance of the device is significantly lower than the internal resistance of a good IMR battery. It can be used with atomizer resistances down to 0.6 Ohms.

Specifications:

• Over-current / short-circuit protection module based around a replaceable, low-voltage-drop polymeric fuse.
• Short-profile 5mm construction, ideal for use with springless, mechanical telescopic mods.
• Silver-plated contacts for the best possible performance.
• Compatible with all mods, side- or bottom-activated.