Single phase, 25 or 40 amp, din rail contactor


  • Maximum Surge Survival™ technology -- triple layer, voltage surge protection
  • Green LED for input status
  • Thermally optimized heat sink permits edge-to-edge installations on a horizontal din rail
  • Built-in snubber circuit
  • Zero crossing activation -- low EMI, low noise to nearby electronics
  • Internal 50A thyristors for high inrush capability
  • 4000 volt isolation, 1400 blocking voltage
  • 1000 volt / microsecond immunity
  • Highest thermal efficiency -- less than 1.0 watt dissipated per amp switched (25 amp model) or less than 1.2 watts (40 amp model)
  • CE, UL recognized, CSA
  • Industry standard A1, A2, L1, T1 terminal numbers
  • High density design permits more amps per square inch
DDA solid state contactor
DDA solid state contactor

Part Number

DDA-6V25   25A, 660V max, 4-32 VDC activated Buy
DDA-6V40   40A, 660V max, 4-32 VDC activated Buy

DAA-6V25   25A, 660V max, 100-280 VAC activated Buy
DAA-6V40   40A, 660V max, 100-280 VAC activated Buy

DDA temperature curver


Part Number Line Voltage Range (VAC) Load Current Range (A RMS) Min Control Voltage & Current Draw Max Control Voltage & Current Draw Must Release Voltage
DC activated
DDA-6V25 24-660 .10-25 4VDC/3.5mA 32VDC/8mA 1 VDC
DDA-6V40 24-660 .10-40 4VDC/3.5mA 32VDC/8mA 1 VDC
AC activated*
DAA-6V25 24-660 .10-25 100VAC/9mA 280VAC/25mA 20VDC/2MA
DAA-6V40 24-660 .10-40 100VAC/9mA 280VAC/25mA 20VDC/2MA
* Typically, does NOT need a burden resistor when activated by a triac output controller.
Off-State dv/dt 1000 v/µs
Isolation 4000 volts
I²T fuse 50A or less, for example: Bussman FWP50A14F, FWC32A10F, FWC20A10F. Ferraz B093910, M330015, K330013. See: I2T fuse and fuse holders
Turn-on time <8.3 ms at 60hz
Turn-off time <8.3 ms at 60hz
Internal MOV The 5V model uses an internal MOV that is similar to the Littelfuse Harris V575 LA80B Metal Oxide Varistor. The use of MOVs is encouraged in situations where there are frequent voltage surges such as motor starter applications. For example: for motor starters, you can use a DDA-6V25 AND an external MOV_V575LA80B (click to buy) OR you can purchase a DDA-5V25, and the MOV will be inside the unit. Contact Power-io for price and availability of this custom variation.
Terminals Will accept #24-#10 AWG wire. Torque: 7-9 inch lbs.
DDA-6V25 and DDA-6V40 size

Zoomed in product picture
Three, din rail solid state contactors and their labels
Schematic of the internal design
Din rail contactor schematic