How to connect a SCEN heater?
Hello. Recently bought a house, next to the garage. A lot of good from the former owner. And plus everything, electrical wiring was carried out, but there was no input. Today I did everything. I determined by the location of the wiring that there are bends from the boxes to the heaters, of which 6 pieces are installed. Not connected. Without measuring the voltage at the terminals, connected one does not work. I checked the heater-worker with a tester. There is no voltage at the terminals. Opened the distribution. boxes (4 pieces) and determined that the heaters are connected in series. One of them has a label with the following marking: SKEN-40-25 TU-21-25-290-85. NOTHING MORE. In addition to the words SCEN and TU, I did not understand anything. What is the operating voltage? Upon reflection, I thought, if they are connected in series, then they are 40 volts each, then it is clear why there are 6. 6x40 = 240. Or I'm wrong? Searches on the Internet did not yield results. Please explain. Thank!
In general, tell us about connecting the device in more detail, since it is not clear what, where, how, and in what sequence.
p.s. I believe that the previous owner simply made a mistake in disconnecting the boxes. In any case, I look forward to more detailed answers to the questions posed above.