Humidity controller and umac

The humidity controller maintains the humidity of the sample at less than 40% using an inline heater and gently heating the airstream. The umac (pronounced micro-mac) is responsible for data acquisition and control.

A document describing the stack heater design is described here. This heater gently heats the sample stream to help lower sample humidity.

Another ‘touch-up’ heater is deployed directly upstream of the impactor box to lower the humidity of the sample air to <40%.

Laptop, umac and humidity controller

Power lights on umac Temperature and humidity readouts on humidity controller	Reset button on umac Power lights on humidity controller