Frigor Tstat Series, Manual

Page: 27 / 56

Tstat Series
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Tstat6: Getting Started
This example will show you how to properly set up a new Tstat6 and attach a couple external devices to the unit. In this
example we will use a DTS-FL-4-6-7 temperature sensor and a PSN 30-300A air differential pressure switch, to be read
by the Tstat6.
1.
2.
3.
4.
Unfasten the screw located at the base of the unit (shown in the diagram) and separate the thermostat from
the backplate. The
fi t is a friction fi t and may be stiff so a fl athead screwdriver can be used to pry the cover
and base apart.
On the backplate locate the power slots at the top right. Loosen the two adjustment screws, with a fl athead
screwdriver and place one wire into the ‘GND’ slot and one wire into the ‘24V’ slot. Tighten the screws down
so the wires cannot be removed and thread the wires through the large rectangular hole in the middle of the
backplate. A connector can be added at the end of the wires to provide an easy method of connecting a 15-
24V AC/DC power supply. The picture on the left below shows an example of what it will look like.
Pick two inputs that you wold like to use for your external devices. We will
choose AI1 for the temperature sensor and AI3 for the pressure switch. The
temperature sensor has two wires. One will be inserted into the AI1 slot and one, the GND slot. It makes no difference
which wire you plug into the slots. Secure the wires the same way as you did for the power cables.
For the pressure switch we will need to determine the characteristics of the device and the pin layout. Of the 3 pins we
need to
fi nd the common pin which should be labelled on the datasheet. For the PSN 30-300A this is pin 1. Using the
multimeter to measure resistance between the common pin and another pin, select the pin combination that produces a
zero ohm resistance. In our case that is pin 1 and pin 3. You can double check if this is correct by blowing into the valve,
making sure that nothing is blocking air
fl ow, and witnessing the resistance change to an in fi nte value. Now connect two
wires onto the probes that we have identi fi ed. You can see two wires have been attached in the middle diagram above.
In this case, green is common so it will be connected to GND on the Tstat6, and yellow will be connected to the input
slot AI3.
Connect the devices to the correct slots on the backplate. When the wires have all been connected, it should look similar
to the diagram above on the right.
Re-attach the backplate to the Tstat6 unit and fasten the screw hold-
ing the backplate securely to the unit.
Connect your power supply, which produces a voltage between 15
and 24 V AC/DC, to the power supply wires you prepared in step 2.
Make sure to connect the positive terminal to the slot that is labelled
24V. Connect the RS485 to a usb port on your computer and then
connect the RS485’s auxilary jack to the port on the bottom of the
Tstat6 unit. The picture to the right shows an exemplary setup.