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Display Temperature & Humidity Logger

This product has been replaced by the DSB

Only download data when you need to with the 24/7 feedback through min/max and real-time display. The TM325 has a remote probe along with audio an visual alarms and flash card data retrieval option.

  • Remote Probe
  • USB enabled downloading
  • Flash memory data transfer capable
  • Jumbo display
  • Easy to use
Tm325 front 662
Tm325 left angle 643
Tm325 rt angle 543
Tm325 rt side 367
Tm325 back 189
Tm325 probe 150
Tm325 sdcard 130
Tm325 top 123

Download Images: Print Quality | Hi-Res

Important Information

DicksonWare Software is needed to communicate with this product and is sold separately.

Dickson Expert Services

Our Dickson Data Division has specially trained representatives to address the needs of customers with large installations or unique demands. Please call 888-452-4626.

  • Alarm Type Audio/Visual on High/Low Temp Limits
  • Ambient Operating RH Conditions 5-95% RH non-condensing
  • Ambient Operating Temperature Conditions -4.0 to 158.0F (-20.0 to 70.0C)
  • Approvals CE
  • Battery Backup Yes, with use of AC Adapter
  • Battery Life (Avg) 6 Months
  • Cable Details USB - Male Series A plug to 5 pin Male Series B mini plug. Serial - 9 pin female D-shell to male 2.5mm stereo plug
  • Cable Length 6.0ft
  • Calibration Options N100, N300, N400, N520
  • Channels CH1: Temperature, CH2: Humidity
  • Data Capacity 32,000 (16,000 per Channel)
  • Dew Point Accuracy +/-3.6F from 30.0 to 95.0% RH (Calculated)
  • Dew Point Range -22.0 to 122.0F (-30.0 to 50.0C)
  • Dimensions 1.6 x 3.0 x 4.0in
  • Display Dimensions Height 1.375
  • Display Dimensions Width 2.0
  • Display Resolution 0.1 from 0.0 to 999.99; 1 over 1000
  • Display Type LCD
  • Display Update Rate 10 Seconds (Battery Power), 1 Second (AC Power)
  • Download Time 1 Minute (USB), 3 Minutes (Serial)
  • Download Type USB / Serial / Flash Card
  • Humidity Accuracy +/-2.0% RH from 0.0 to 60.0% (+/-3.0% RH from 60.0 to 95.0%)
  • Humidity Range 0-95% RH non-condensing
  • Humidity Sensor Type Monolithic IC Humidity Sensor
  • IP Rating 20
  • Included Accessories Four AA Batteries, Remote Probe and Quick Start Guide. *Software is not included.
  • Memory Type EEPROM, Removable Flash Storage Device
  • Minimum Software Version Required 8.3
  • Mounting Options Wall Mount (With Keyhole)
  • PC Requirements HelpMicrosoft Windows 98 or newer, 16 MB RAM, 1 free COM (serial) port with dedicated interrupt or 1 USB root hub, CD drive, VGA monitor or better
  • Power Source Four AA Batteries (User Replaceable) *AC Adapter is not included, but can be used.
  • Power Source Notes AC Power is optional, but not included.
  • Power Status Indicator LCD Display
  • Remote Probe Dimensions Houses thermistor and RH sensor in polycarbonate plastic; 1.5" x 0.5" (1.25cm x 4.5cm)
  • Remote Sensor Length 10 ft
  • Remote Sensor Type Thermistor
  • Response Time 1 Minute to 63% of Full Scale
  • Sample Interval User Selectable (from 1 second to 24 hour intervals, in 1 to 10 second increments).
  • Software Options A015, A025, A016, A026
  • Temperature Accuracy +/-0.8F from 20.0 to 120.0F 1.8F
  • Temperature Range Help-40.0 to 185.0F (-40.0 to 85.0C)
  • Temperature Sensor Type Thermistor
  • Unit Weight 3 lbs
  • Units/Pkg 1
  • Warranty 12-Month Limited
Why should I calibrate?

All instruments lose accuracy over time due to normal usage and the environmental conditions to which they are exposed.

How often should I calibrate?

For most applications, the recommended calibration interval is every twelve months.

N100 1-Point NIST Traceable Calibration $99.00 Add
N300 3-Point NIST Traceable Calibration $156.00 Add
N400 3-Point Ultima NIST A2LA Accredited Calibration $269.00 Add
What is NIST Calibration?

NIST stands for the National Institute for Standards and Technology. This organization is responsible for maintaining the master for different measurements, such as the standard "foot", standard, "second", or standard "pound". NIST also maintains the standard for temperature, humidity and pressure.

NIST Traceable means that the measuring standard can be traced directly back to the master standard maintained by the NIST organization.

NIST-Traceable does not tell you the measurement accuracy of a metrologty service in any detail. Only metrology services that can document their ISO 17025 standard provided data on their best measurement uncertainty.

AC Adapter Extension Cable 10'

10' Power Extension for R157 AC Adapter

AC Adapter

AC Adapter

Universal Plug Kit for AC Adapter

Set of Three International Power Plugs for AC Adapter

AA Battery

AA Alkaline Battery

Probe Dust Filter

Probe Dust Filter - prolong the life of your instrument.

Card Reader Kit

Includes USB Reader and Flash Memory Card

Memory Card

Removable Flash Memory Card

AA Batteries

4 Pack AA Lithium Batteries

USB Download Cable

USB Download Cable - length 6 feet (2m)

Serial Download Cable

Serial Download Cable - length 6 feet (2m)

Secure Software

DicksonWare Secure Software with USB Cable


DicksonWare Software with USB Cable

Frequently Asked Questions

Check your software version. Versions prior to 11.4 contained a bug that caused the email communication to fail if the email address was over a certain length. Contact customer service for an upgrade.
Untitled Document
  • This is normal when the probe is not connected at the time a sample is taken.
The TM325/725 will only communicate if the probe is connected.
  •  Press and hold the Min/Max button for 5 seconds.

Flash cards not purchased through Dickson should be formatted. If formatted after experiencing issues the unit will have to come back to be reset.

Formatting instructions:
1. Insert flash card into card reader
2. Go to My Computer and right click on the drive letter that corresponds with the card
3. A menu will appear. Choose the format option
4. Another window will appear
5. Under the "File System" heading, drop down the menu and choose the option, if running Windows XP. Choose "FAT" if running Windows 7 or 8.
6. Then click on the start at the bottom of the window

This will format the card in the correct manner for use with the unit.

Err 1 - No memory card
Err 2 - Memory card locked or protected
Err 3 - Wrong size file (too big) or no data to log yet
Err 5 - Trouble writing file to card
Err 14 - This is a generic fault code. There is something wrong with the card (full or not formated correctly) or there is a hardware issue (a bad connector or no card present - can't see any card). Try another card.
Err 16 - Trouble accessing card
Err 23 - Memory card requires reformatting
Err 7 or 66 - Memory card full
Err 49 - Unknown error

The Flash Memory Download Feature was designed to work with standard MMC cards. MMC Plus cards can cause the unit to stop logging when used to download data. If you think the unit stops logging when the Flash Memory Download Feature is used, you might be using a MMC Plus card. We recommend using Dickson Flash Memory Cards.

The min/max on the display is not the min/max alarm settings. The min/max on the display shows the temperature or temp/Rh min/max only.
The more files stored on the card, the slower the download. It's a good idea to clear the memory card occasionally.

Verify that you have the correct version of DicksonWare software installed on your PC. Version 8.0 for all units except the Net Loggers which require Version 9.0

Verify that the correct COM port is selected: From the main Dicksonware screen, click on Logger then Communication, a black dot will appear next to the selected COM port. You may need to select a different COM port. Should you get an error message stating that Device Is Already Open, this could mean that you have the proper COM port selected, but another device, or its software, has it allocated. Palm pilots, for example, will cause this problem, in which case the port is not actually available and you may have to disable that device.

You may need to relocate the download cable to another serial port on the back of the PC and possibly try changing the COM port again in DicksonWare.

If communication has not been established with the previous steps, you may need to remove the batteries and then try all COM port and cable combinations again.

If possible, try another PC

Make sure the USB is unplugged, and that USB is NOT checked in File > Preferences > Serial.

Try removing the batteries and ac power (if applicable) for a few moments, (this will not cause the unit to lose any data within the logger, but you will have to start the unit logging again using DicksonWare).

Batteries may be too low, replace batteries.

Unplug USB cable and plug back in.

If the logger was used in a moist or humid environment condensation may have formed on the unit. Place unit in a warm dry environment for 24 hrs. Clear memory and try again. These loggers are designed for use in a non-condensing environment. If the environment creates condensation, try placing the unit (temperature only models) in a small sealed plastic bag to protect it from condensation.

In order to view units over multiple subnets or to view units on non-standard subnet mask, click on the Connect button then select Set Subnet. You can enter a different Subnet here. DicksonWare will not remember this address, and it will need to be re-entered every time you open a new DicksonWare session.

When the IP address is set using USB and the logger is then connected to the network, the logger will not be detected until all power (AC and battery) is removed and the unit is then powered on again.

Is the probe plugged in properly?

Is there an extension cable being used? It could be defective

Chart Recorders

It may be locked up? This can be confirmed by pressing any of the buttons on the keypad, if the unit is locked up there will be no response to button presses and the unit may appear to be working, but the readings won't change, also the chart will not rotate. Remove power and battery, and then re-power.

The sensor board may have fallen out or become partially unplugged. Remove the back panel, the sensor board should be plugged in the center of the main board. If the sensor board is in its socket, you may need to ensure the connection by pressing down on it to make sure it is secure. The pens should respond right away if this is the only cause of the problem.

Is the probe plugged in properly?

Is there an extension cable being used? It could be defective.

Replace the batteries, they may be low.