The Delta speed sensing relays are designed as protection equipment for diesel engine or similar rotating machinery where several speed levels must be detected.
The relays accept an input signal from a tacho generator or similar AC or DC voltage source, the output voltage of which is proportional to engine speed. VDO tacho generator type 2.340 or equivilent is suitable.
Three relays within the unit operate at preset levels to provide functions normally related to starter motor cut-out, underspeed and overspeed. The relay requires a DC voltage of 12 or 24 volts negative ground. 12 or 24 volt positive earth systems may be used but the tacho generator must be unearthed and the winding returned to terminal 1.
With the DE002 the starter cutout and underspeed relays are energised at rest and are de-energised at the set speed as speed increses. The DE007 operates in reverse to this.
On falling speed, starter cutout and underspeed realys will energise as the speed passes through set levels but on rapidly falling speed a 3 second non-adjustable timer delays operation of both relays.
The overspeed relay is latched if the speed rises above the set point, it is reset by breaking the positive supply.
|Supply voltage:||12 or 24V DC (specify when ordering)|
|Starter cutout speed:||700 or 350 rpm (specify when ordering)|
|Nominal tacho generator speed:||1500 or 750 rpm (specify when ordering)|
|Underspeed relay operates at:||1350 or 675 rpm (specify when ordering)|
|Overspeed relay operates at:||1650 or 825 rpm (specify when ordering)|
|Relay contacts:||Single changeover contact, 5Amp resistive.|
|Inductive loads must have diode suppression.|
|Adjustment:||Potentiometers – variations of +/-10% from presets|
|Dimensions:||155mm(L) x 128mm(W) x 55mm(H)|
|Finish:||Grey hammer tone stoved enamel|