
Labkotec SET-1000 12 VDC Level Switch Sensor 
General Information
SET-1000 is a one-channel level switch. Typical applications are high-level and low-level alarms in liquid tanks, condensed water alarms, level control, and alarms in oil, sand, and grease separators.

Installation
The SET-1000 can be wall-mounted. The mounting holes are located in the base plate of the enclosure, beneath the mounting holes of the front cover. The connectors of the external conductors are isolated by separating plates. The plates must not be removed. The plate covering the connectors must be installed after executing cable connections. The cover of the enclosure must be tightened so that the edges touch the base frame. Only then do the push buttons function properly, and the enclosure is tight. Before installation, please read the safety instructions in the chapter!
Using Junction Box
This point can be connected to the equipotential ground through the ground terminal. Other components of the system that need to be grounded can also be connected to the same ground terminal. The wire used for equipotential grounding must be a minimum. 2.5 mm²mechanically protected or, when not protected, the minimum cross-section is 4 mm². Please make sure that the cable between SET-1000 and the sensor does not exceed maximum connection values – see Appendix 2. Detailed cabling instructions can be found in the instructions of particular Labkotec SET sensors.

Level sensor cabling with a junction box for the cable extension. The junction box of type LJB2 includes light alloy parts.
Using Cable Joint
Please make sure that the sensor and cable between the ET-1000 control unit and the sensor do not exceed the maximum allowed electrical parameters – see Appendix 1, Technical data. IP rating of the cable joint is IP68.

Installation accessories, Level sensor cabling with a cable joint for cable extension
Setting
See a more detailed description in chapter 3.1 Operation. Channel 1 Alarm takes place when the level hits the sensor (high-level alarm). The trigger level is normally at the middle of the sensor’s sensing element.
Operation
If the operation is not as described here, check the settings (chapter 3) and the operation (chapter 4) or contact a representative of the manufacturer. Normal mode – no alarms. The level in the tank is below the sensor.
The main LED indicator is on. Other LED indicators are off. High-level alarm: The level has hit the sensor (sensor in the medium). The main LED indicator is on. Alarm LED indicator is on. Buzzer on after 5 5-second delay. Relays de-energize after 5 5-second delay.
Fault alarm: Sensor cable break, short circuit, or a broken sensor, i.,e. too low or too high sensor signal current. The main LED indicator is on. Sensor cable Fault LED indicator is on after 5 5-second delay. The relays de-energize after 5 5-second delay. The buzzer is on after 5 5-second delay. Reset the alarm when pressing the Reset push button. The buzzer will go off. Relay 1 energizes.
Relay 2 will stay de-energized until the actual alarm or fault is off..The test function provides an artificial alarm, which can be used to test the function of the SET-1000 level switch and the function of other equipment that is connected to SET-1000 via its relays.
Normal situation
When pressing the Test push button, the Alarm and Fault LED indicators are immediately on. The buzzer is immediately on. Relays de-energize after 2 seconds of continuous pressing. Relays energize immediately
Alarm on
When pressing the Test push button, the Fault LED indicator is immediately on. Alarm LED indicator remains on. Buzzer remains on.
The test will not affect relay 2, because it is already in alarm status. Fault alarm. When pressing the Test push button, the device does not react to the test at all.
Altering settings
Operating direction: High-level or low-level function (increasing Labkotec SET-1000 12 VDC Level Switch Sensor or decreasing level). Operation delay: Two alternatives: 5 sec or 30 sec.
Trigger level: Trigger point of an alarm in the sensor’s sensing element.

Direction Mode
Repair & Service
The mains fuse (marked 315 mAT) can be changed to another Labkotec SET-1000 12 VDC Level Switch Sensor glass tube fuse 5 x 20 mm / 315 mAT complying with N IEC 60127-2/3. Any other repair and service work on the device may be carried out only by a person who has received training in Ex-i devices and is authorized by the manufacturer.r
Troubleshooting
- Problem: The MAINS LED indicator is off.
- Possible reason: Supply voltage is too low or the fuse is faulty. The transformer or MAINS LED indicator is faulty.
- To do: Check if the two-pole mains switch is off. Check the fuse. Measure the voltage between the n poles + and -.
- Problem: FAULT LED indicator is on.
- Possible reason: Current in the sensor circuit too low (cable break) or too high (cable in short circuit).
- To do: Measure the voltage separately between the poles 10 and 11. The voltages should be between 10,3….11,8 V. 3. If the voltages are correct, measure the sensor current.
- Do as follows: Disconnect the sensor’s [+] wire from the sensor connector (pole 10). Measure short circuit current between [+] and [-] poles. Make a comparison Labkotec SET-1000 12 VDC Level Switch Sensor to the values in the Table.

Appendix 1 Technical data
| SET-1000 | |
| Dimensions | 175 mm x 125 mm x 75 mm (L x H x D) |
| Enclosure | IP 65, material polycarbonate |
| Cable glands | 4 pcs M16 for cable diameter 5-10 mm |
| Operating environment | Temperature: -25 °C…+50 °C Max. elevation above sea level 2,000 m Relative humidity RH 100% Suitable for indoor and outdoor use (protected from direct rain) |
| Supply voltage | 11-17 VDC Fuse 5 x 20 mm 315 mAT (EN IEC 60127-2/3) The device is not equipped with a mains switch |
| Power consumption | Max. 1,2 VA. Typical (no alarms) 0,9 VA. |
| Sensors | One Labkotec SET sensor |
| Relay outputs | Two potential-free relay outputs 250 V, 5 A, 100 VA Operational delay 5 sec or 30 sec. Relays de-energize at the trigger point. The operation mode is selectable for increasing or decreasing the level. |
| Electrical safety | EN IEC 61010-1, Class II , CAT II / III POLLUTION DEGREE 2 |
| Insulation level Sensor / Mains supply voltage | 375V (EN IEC 60079-11) |
| EMC Emission Immunity | EN IEC 61000-6-3 EN IEC 61000-6-2 |
| Ex-classification Special conditions (X) ATEX IECEx | II (1) G [Ex ia Ga] IIC (Ta = -25 C…+50 C) EESF 21 ATEX 022X IECEx EESF 21.0015X |
| Year of manufacture See the serial number from the type plate | xxx x xxxxx xx YY x where YY = year of manufacture (e.g. 19 = 2019) |
Appendix 2 Electrical parameters
When installing the device, make sure that the electrical values of the cable between SET-1000 and the sensor never exceed the maximum electrical parameters. The table below indicates the connecting values in explosion groups IIC and IIB. Uo = 14,7 V Io = 55 mA Po = 297 mW R = 404 Ω The characteristics of the output voltage is trapezoidal

The maximum length of the sensor cable is determined by the resistance (max. 75 Ω) and other electrical parameters (Co, Lo, and Lo/Ro) of the sensor circuit.
. 81 Ω / km. – Inductance is approx. 3 μH / m. – Capacitance is approx. 70 nF/km Influence of resistance. The estimate for additional resistances in the circuit is 10 Ω.
The max length of the cable is then (75 Ω – 10 Ω) / (81 Ω / km) = 800 m. The influence of inductance and capacitance of a oa800 m cable is: Influence of inductance. Total inductance is 0,8 km x 3 μH/m = 2,4 mH. The sum value of the cable and e.g,. SET/OS2 sensor [Li = 30 μH] is 2,43 mH. L/R ratio is thus 2,4 mH / (75 – 10) Ω = 37 μH/Ω, which is less than the maximum allowed value 116,5 μH/Ω. Influence of capacitance Cable capacitance is 0,8 km x 70 nF/km = 56 nF.
Combined value of the cable and the e.g., SET/OS2 sensor [Ci = 3 nF] is 59 nF. When compared to the values in Table 2, we can summarize that the above values do not limit the use of this particular 800 m cable in explosion groups IIB or IIC.
Customer Service
- E-mail: labkonet@labkotec.fi
- Tel: +358 29 006 6066.
- Address: Myllyhaantie 6, FI-33960 Pirkkala, Finland
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FAQs
What power supply does the SET-1000 require?
The power source for the SET-1000 is 12 VDC. To avoid damage or malfunctioning operation, make sure the power source is steady and meets the designated voltage.
Can the SET-1000 be used with both conductive and non-conductive liquids?
It might be necessary to use a different kind of level sensor for non-conductive liquids.
Is the sensor suitable for outdoor or harsh environments?
To be sure it satisfies the specifications for your particular area, however, look up the IP rating in the user manual.
What type of output signal does the SET-1000 provide?
When the liquid level surpasses the predetermined threshold, the relay output used by the SET-1000 changes states.
Does the SET-1000 require regular maintenance?
It needs very little upkeep. Periodically clean the sensor probe to remove buildup or scaling that could impact conductivity and detection accuracy.





