PPM-2 Meter with Short-UV-Wavelength External Sensor

This handheld meter has an external, low-profile UV sensor, a large, easy-to-read display showing the exposure data, and a start-stop button. The sensor on the unit measures only the UV wavelengths between 240 - 370 nm while not responding to visible light. As well as measuring UV intensity in this wavelength range, the meter also measures the exposure time and the accumulated (integrated) exposure dose. 

This meter is designed primarily for use with vacuum frame systems where the sensor must be as thin as possible to fit inside the frame and has a thin, flat cable that can pass underneath the seal.

The meter is extremely simple to use: Repeated pressing of the green Start/Stop button will toggle the meter between its three modes: 

  1. Reset:  All readings are reset to zero; 
  2. Measure:  The display now shows the current UV intensity, the time in seconds and the accumulated UV dose since the measurement started.
  3. Hold:  The measurement is stopped and the measurements are frozen on the display to allow you to record the information if you choose.
  4. A further SHORT press will return you to step 2 to allow you to continue a measurement (useful for checking progress or while making test-strips), or a LONG press (3 seconds) will take you back to step 1 and reset the meter.



Spectral response of the sensor, and the emission characteristics of a range of suitable light sources.


System:  The PPM-2 consists of a control unit driven by a microprocessor, an external light sensor with an 18" flat-cable, a 36" extension cable, a removable telescoping handle, a protective case and instructions.

Dimensions:   Control unit: 5.7" x 3.5" x 2.1" (length x width x thickness), External sensor:  1.5" x 0.9" 0.18" (4.5mm) 

External Sensor:  Has a thin-flat cable intended to pass underneath the seal of a vacuum frame. It has an integral magnetic latch allowing the optional attachment of a telescoping handle to reach inaccessible spaces (handle is provided). Also the sensor head will attach magnetically to the front of the control unit making it convenient for measuring in less restricted spaces (please see the photos below). The sensor is removable for storage. The display indicates 'No Sensor' if measurements are attempted without the sensor being attached.

Spectral Response:    240 - 370 nm. Suitable for use with mercury bulbs, blacklights, Philips' Actinic 05 bulbs, the sun or similar light sources.

Exposure dose: This is the reading that will be of most frequent use to the artist. It is the total accumulated UV dose received by your print medium since you pressed the start button. Monitoring the dose during the exposure process and stopping once you reach the 'target dose' ensures your prints always receive the same exposure regardless of the intensity of the illumination.

Intensity: This reading has many uses: evaluating the intensity of ambient UV levels in the studio, measuring the relative UV transmission of materials, or comparing the UV intensity of different light sources. 

Time:  This reading is the number of seconds since you started the measurement.

Battery Operation:  Operates from a standard 9V battery, which is easily replaceable without tools. The display indicates a 'Low Battery' warning once the battery voltage has dropped below 5V indicating the battery should be replaced.

Sleep Mode: the meter will go into sleep mode after 5 minutes of inactivity in order to preserve the battery. Note that this will not happen if you are in the process of making a measurement. Simply press the green button to restore.

The Display: Consists of a backlit 16 x 2 green display for easy reading. The information shown is the time (in seconds since the measurement started), the current UV intensity level, and the accumulated dose of UV light received since the measurement started.

       The external sensor is 0.18" (4.5mm) thick, with a 1mm thick flat cable.

     The external sensor will attach magnetically to a telescoping handle for measuring in tight spaces.

  The external sensor also attaches magnetically to the front of the control unit for convenience when measuring sources such as the sun.