The Winland MTA-1 is a dual-output temperature sensing device that can be set to monitor both high and low temperature conditions. It does not require input power in order to operate. It has two (2) outputs, one for low-temperature, and one for high-temperature alarms. Do not use in a freezer.
Mechanical means that the MTA-1 has moving parts. For this reason, it is not meant to operate in a walk-in cooler or freezer. If you need to monitor the temperature in one of these locations, it is recommended to use either the Winland EA200 or the Winland EA400. These devices have remote probes that will mount inside the cooler or freezer while the body of the sensor itself is mounted outside.
When choosing an installation location, a good rule-of-thumb is to install the MTA-1 near an existing thermostat that is being used for environmental control. If multiple thermostats are in use, then multiple MTA-1 units should also be used. When using the MTA-1 to monitor for freeze detection in a multi-story building, at least one device should be mounted on each floor.
To install the Winland MTA-1, you will need a standard flathead screwdriver, a 5/16" wrench or nut driver, and 18 - 22 AWG twisted pair wire (assuming you will be connecting the alarm output to an alarm device). The alarm output for the MTA-1 is two (2) Normally Open (NO) dry contacts with a contact rating of 50 mA @ 12VDC. Prior to installation, you will need to remove the front cover from the device. Holding the device facing you, press your right thumb onto the left end of the device. You'll notice there is a wire routing hole there. Press in hard with your right thumb, then pull the front away from the back by grasping the back with your left hand and pulling the front forward with your right. You can now attache the base to the mounting surface.
Looking at the rear of the front portion of the MTA-1, you'll see the adjustment points for both high and low temperature. Using the 5/16" wrench or nut driver, loosen the locknut for the desired set point by turning counter clockwise, then slide the set point forward or back to the appropriate temperature setting. Once the proper setting is achieved, tighten the locknut again by turning it clockwise. Do not over tighten. Failure to tighten the locknut will result in unpredictable results. Generally, there should be at least a 10 degree difference between the high-temperature set point and the low-temperature set point.
To connect to an alarm panel, there are three terminals available on the unit. COM, HI, and LOW. These represent Common, the High-Temperature alarm output, and the Low-Temperature alarm output. You can choose to use only one of these outputs, you can choose to connect both outputs to a single alarm zone if you don't care to distinguish between a high or low temperature alarm, or you can connect each output to a separate zone. Once the set points have been adjusted, and the wires have been connected at the MTA-1, you can mount the front of the device to the base plate. Refer to the installation instructions of your alarm panel for proper wiring for a NO contact or contacts.
- Power Requirement:No power is required for this device.
- Low Limit Adjust Range: +30℉ - +90℉ (-1℃ - +32℃)
- High Limit Adjust Range: +40℉ - 100℉ (-4.4℃ - +37.7℃)
- Temperature Accuracy: ±3℉ (±1.7℃)
- Temperature Sensing Element: Bimetallic Coil
- Outputs: Two (2) Gold plated, Normally Open, Dry Contacts (Not for High Voltage Use.)
- Contact Rating: 50mA @ 12VDC
- Weight: 6oz (.17kg)
- Dimensions: 4.5" x 3.25" x 1" (11.4cm x 8.3cm x 2.5cm)
- Case Material: ABS