Working on HVAC systems, refrigeration, or vacuum chambers? The Welch 1515A is a classic, reliable thermocouple gauge for measuring rough to medium vacuum. It's the go-to tool for many technicians.
It measures from atmospheric pressure down to 0.1 Torr (which is 100 microns, but its scale reads up to 5000 microns/motor for the higher pressure range). The principle is simple: a heated wire in the gauge tube cools as gas molecules hit it, and that change translates to a pressure reading.
This model is portable and lightweight, powered by a standard 9V battery. A really useful feature is the 0-10VDC recorder output on the back, which lets you connect it to a chart recorder or data logger to track vacuum over time.
It comes with one gauge tube permanently attached. It's straightforward, durable, and made in the USA by a trusted brand in vacuum technology. If you need a no-nonsense gauge for evacuation, leak checking, or process monitoring, the Welch 1515A is a professional staple.
