Dwyer GDL - Manual (Page 18)

DwyerLog User’s Guide Versin 1.2x 18/25
MTL-30 Temperature Humidity Logger
The MTL-30 is a self-contained, precision instrument for recording the temperature and relative humidity of the
surrounding environment. The MTL-30 can store up to 43,344 temperature samples, or up to 21,672 of both
temperature and relative humidity samples. In addition to Temperature and Humidity, the DwyerLog software
computes and displays the Dew Point Temperature.
The MTL-30 logger temperature and relative humidity sensors are open to the air. It is therefore important to ensure
that water does not get into the unit. This is especially important in high humidity situations (90% RH and above)
where water may condense inside the logger, causing damage to the internal electronics.
Warning: Care must be taken to ensure that the logger is not operating under condensing conditions. This
means that the dew point temperature must be below the ambient temperature. Condensation will damage the
humidity sensor and the logger electronics.
Replacing the MTL-30 Battery
The battery level of the MTL-30 can be checked using the DwyerLog software, by opening the Logger Status
window. It is suggested that the battery is replaced when the battery level reaches yellow. When the battery level
reaches red, it is imperative that the battery is replaced as soon as possible. When the battery level is too low, the
logger will stop logging automatically, resulting in data not being recorded. The DwyerLog software will give you a
warning if you try to start a logging session while the battery is low.
To replace the battery follow these steps:
1. Disconnect the logger from the USB cable. Do not replace the battery while the USB cable is connected!
2. Using a screwdriver, remove the screw in the back of the logger.
3. Remove the logger from the case.
4. Using a pen or a pencil, push the battery out of the casing, then use your fingers to slide the battery out
Avoid using pliers as they will short the battery.
5. Press and hold the logger button for about 2 seconds. This step removes any extraneous charge from the
logger system. This step is very important. The logger may not operate correctly if this step is not
performed.
6. Slide the new CR2032 battery into the battery case. Make sure that the + indicator on the battery matches
the + indicator on the battery case.
7. When the battery is replaced correctly, the LED will flash a single green flash for about 1 second.
8. Place the logger back in the case and replace the screw.
General guidelines as to how long a battery will last is shown in the table below. It is assumed that the logger uses a
fresh CR2032 battery, and is setup for continuous logging with rollover enabled.
Logging Interval Battery Life
1 Second
4 Months
5 Seconds 17 Months
10 Seconds 2.5 Years
30 Seconds 4.5 Years
1 Minute 6 Years
2 Minutes 7 Years