MMT330 - Temperature and humidity sensor VAISALA - Free user manual and instructions

USER MANUAL MMT330 VAISALA

Vaisala Transmitters

HMT330, DMT340, MMT330

About This Quick Guide This Quick Guide provides an overview on how to install Vaisala HUMICAP® Humidity and Temperature Transmitter Series HMT330, Vaisala DRYCAP® Dewpoint and Temperature Transmitter Series DMT340 and Vaisala HUMICAP® Moisture and Temperature Transmitter Series for Oil MMT330. Please refer to the relevant User's Guides for detailed information on the use of the products. difference in temperature between the environment and the probe can cause an error of several percentages in RH. Mounting the Probes with Cable Mount the probes with a cable with the sensor head horizontally or vertically. This way, any water condensing on the tube cannot flow onto the sensor. When installing probe into a chamber with a higher T than the surrounding the point of entry must always be carefully insulated. The cable must also be allowed to hang loosely as this prevents any condensed water from running onto the sensor head along the cable. Things to Consider When Measuring Dewpoint - If a sampling system is built instead of direct probe installation, it is important that the system is leak-proof. Recommended material for sampling system construction is stainless steel. Also PTFE may be used down to dewpoints of -40°C / -40 °F. - Dewpoint is a pressure dependent parameter. It is important that the pressure at the sensor is the true process pressure. The temperature is not of major importance, as long as it is above the process dewpoint in order to avoid condensation. When Measuring Relative Humidity In humidity measurement it is essential that the temperature of the probe and the measured gas is the same. Even a small 0507-024 Figure 1 Horizontal Mounting of Sensor Head Numbers refer to Figure 1 above.

To be sealed. To be insulated. Insulate the cable. Let the cable hang loosely. This prevents condensed water running to the sensor along the cable. - Refer to the appropriate User's Guides for further installation instructions for probes with a cable as well as other installation possibilities. VAISALA ________________________________________________________________________3

When Measuring Moisture in Oil - The measurement should be done in a location that provides a representative sample of your entire oil system (for example, a high flow feed line or return line to reservoir). The sensor reads that which it is in contact with only. Transmitter Housing Standard Installation Mount the housing by fastening the transmitter to the wall with 4 screws, for example M6 (not provided). Refer to the User's Guides for the use of the optional mounting plates. - Locations to avoid include the bottom of oil reservoirs and bends in a pipeline where free water may settle out as well as areas where heavy air bubbling could occur due to turbulence caused by pumps or agitators. 0510-026 Figure 2 Standard Mounting Dimensions (in mm/inch) Operation 0503-023 Figure 3 Inside of the Open Transmitter Numbers refer to Figure 3 above.

Service port (RS-232) Dip switches for analog output settings Power supply and signal wiring screw terminals Relay/RS-485 module (optional) Grounding connector Power supply module (optional) Relay module/third analog output module (optional) Probe Output isolation module/DC-DC converter (optional) Adjustment buttons with indicator led 4 ___________________________________________________________________ M210742EN-A

A single electrical cable with a screen and three to ten wires is recommended for power and analog/serial connections. The cable diameter should be 8...11 mm. The number of cable bushings depends on the transmitter options. Ground the screen of the electrical cable properly to achieve the best possible EMC performance. Cut back outer sheath to desired length. 0504-049 Figure 4 Grounding the Screen of Electrical Cable

Cut back screen braiding or screen foil to dimension X (see figure 2).

Push the domed cap nut (item 1) and the seal insert with contact socket of the gland (item 2+3) onto the cable as shown in the diagram.

Bend over the screen braiding or screen foil by about 90º (item 4).

Push the seal insert with the contact socket of the gland (item 2+3) up to the screen braiding or screen foil.

Mount lower part (item 5) on the housing.

Push the seal with the contact socket of the gland and (item 2+3) flush into the lower part (item 5).

Screw the domed cap nut (item 1) onto the lower part (item 5). When connecting to a 24 VAC power supply a separate floating supply for each transmitter is recommended. WARNING The AC (mains) power connection may be connected to the power supply module only by an authorized electrician. WARNING Make sure that you connect only unpowered wires. CAUTION In case you have only one AC supply, never connect same wire to the + connector of a transmitter and to the - connector of another one. This will short-circuit the transformer. VAISALA ________________________________________________________________________ 5

Starting Operation - Within a few seconds after power-up the led on the cover of the transmitter is lit continuously indicating normal operation. When the transmitter equipped with a display is turned on the first time, the language selection window opens. - Select the language with arrow buttons and press the SELECT button. Maintenance

The transmitter is fully calibrated and adjusted as shipped from factory. - Calibration must be done always when there is a reason to believe that the device is not within the accuracy specifications. Calibration and adjustment can be carried out in Vaisala Service Centers or by the user NORTH AMERICAN SERVICE CENTER, phone: +1 781 933 4500 EUROPEAN SERVICE CENTER, phone: +358 9 8949 2658 0511-114 Figure 5 Language Selection Menu - The pressure has an effect on humidity calculations and accuracy. Therefore, accurate calculations can be achieved only when the process pressure is taken into account. TOKYO SERVICE CENTER, phone: +81 3 3266 9617 BEIJING SERVICE CENTER , phone: +86 108526 1199 www.vaisala.com - In DMT340, the start-up time is about 6 minutes due to a self-diagnostics procedure. During this, the outputs are frozen. 6 ___________________________________________________________________ M210742EN-A