AC Voltage Stabilizer Modalis MR 400ST



Modalis MR 250ST AC voltage stabilizer 


Modalis MR 250ST single-phase AC voltage stabilizer is part of the Modalis product range of Thermo-Sim (ST) voltage stabilizers.

Modalis MR 250ST voltage stabilizer is designed for protection of different types of energy-dependent boiler equipment with aggregate power consumption of no more than 250 VA (control relays of gas boilers, circulation pumps, etc).

Modalis MR 250ST voltage stabilizer is designed as a wall-mounting unit with indicator display on the front panel, one European power socket on the side panel, and power switch and automatic fuse on the bottom panel. It's equipped with a Europlug power cable.



     Design features:

  • wall-mount enclosure (mounting bracket included);
  • toroidal power autotransformer;
  • quiet operation;
  • increased reliability and durability;
  • double load protection from critically high input voltage;
  • automatic disconnection of autotransformer in case of input voltage surge over 300V with subsequent automatic reactivation once safe voltage has been restored;
  • self-cooling (no fan);
  • discrete (step-by-step) adjustment of output voltage;
  • wide range of input voltage;
  • high overload capacity;
  • TRIAC power circuits;
  • fast response time;
  • electronic overload and short-circuit protection featuring automatic disconnection and subsequent nonrecurrent automatic reactivation;
  • ability to work at declared load power within the entire range of input voltages;
  • automatic power cutoff when input or output voltage exceeds the preset threshold with subsequent automatic reactivation after voltage is restored to levels within the allowed range of operation;
  • output power filter to suppress high frequency distortions;
  • LED indicators of operating modes;
  • European power socket to connect the load; Europlug power cable to plug into the power circuit.


Product specifications

Number of phases 1
Maximum load capacity, kVA 0,25
Admissible overload 100% - 10 s
Effective range of input phase voltage, V 175-275
Extreme range of input phase voltage, V 160-285
Rated input frequency, Hz 50
Input frequency range, Hz 48-52
Maximum off-load current with input voltage of 220V, mA 52
Output phase voltage stabilization, % ±4,5
Effective range of output phase voltage, V 220-240
Extreme range of output phase voltage, V 200-252
Number of correction levels 7
Energy conversion efficiency, % 95
Range of load change, % 0...100
Load power factor 0-1
Type of switches TRIAC
Time of voltage adjustment for one correction level, ms <=40
Overload and short-circuit protection electronic, with automated switch
EMI/RFI filter input
External temperature range, °С +1...+40
Relative air humidity, % 0...80
Cooling procedure self-cooling
Protection rating IP30
Weight, kg 3,6
Overall dimensions (WxHxD), mm 205 x 240 x 72
Overall dimensions in packaging (WxHxD), mm 265 х 265 х 120
Warranty, months 24
Service life period, years 10


pdf Manual
pdf Certificate