Cooper QD3 User Manual

QD3 Quik-Drive Voltage Regulator Tap-Changer Manual
6
The reversing moveable contact assembly consists of
the reversing segment, neutral main stationary contact,
and reversing moveable contact. The reversing moveable
button-contact makes or engages the reversing station-
ary contacts as the tap-changer is moved off of the Neu-
tral Position. The other end of the moveable contact has
a button contact that stays engaged with the neutral sta-
tionary contact at all times.
If the neutral stationary contact is in need of being
replaced, the complete reversing switch moveable con-
tact assembly should be replaced.
Micro-Switchs
Micro-switches are use for the holding switch, reversing
logic, neutral indication, and taping limit logic switches.
Two sets of normally closed switches are used to pro-
vide a safety switch circuit to prevent the tap-changer
from trying to tap beyond 16R and 16L. This assists the
mechanical stop. These two switches allow the tap-
changer to reverse in the opposite direction when the
mechanical stop is reached, causing the holding switch
to become closed.
The micro switches used are rated for –40°C to 130°C,
5 mp 125/250 Vac rating. The switches are designed
to exceed one million operations at QD3 tap-changer
current.
Housing, Geneva, Gears, Cams
and Bearings
Housing, geneva, gears, cams and bearings are con-
structed of reinforced thermoplastic engineered grade
polymer providing these characterizes.
 •Transformeroilcompatible
 •Envirotemp™FR3™uidcompatible
 •Highheatresistancewithanoperating
temperature over 200 °C
 •Highmechanicalstrength
 •Highelectricalcreepresistance
 •Moldedpartreducesnumberoftotaltap
changer parts
 •Lowerwaterabsorptionandpowerfactorthanphenolicboard
 •Goodmechanicalcreepresistance
 •Corrosionresistant
 •Highdielectricstrength
 •Goodwearresistance
 •Highchemicalresistance
 •Sometypicalapplicationsinclude:
  •Under-hoodhightemperatureautomotive
applications such as engine manifolds
  •Electricalapplicationssuchascircuitbreakersand
stand-off insulators
  •Hightemperaturelightingapplications
QD3 Drive Mechanism
Once a tap change is initiated, a holding switch energizes
the motor through a separate circuit until the indexing
motion is completed. The indexing occurs very fast. The
total elapsed time to complete the action is approximately
270 milliseconds from the time the indexing signal is
started by the control. The motor turns a Geneva drive
gear that is coupled to the motor shaft. Each full turn of
the Geneva drive gear rotates the main Geneva/contact
drive assembly 20°C. The moving contacts are assem-
bled directly to the main Geneva/contact drive assembly.
This direct connection achieves accurate indexing of the
contacts.
The permanent magnet rotor arrests the inertia of the
system once the tap change is completed and the power
is removed from the motor. A safety switch circuit and a
backup mechanical stop prevents rotation of the main
Geneva/contact drive assembly beyond the maximum
position.
Neutral Main
Stationary
Contact
Figure 8.
Reversing switch moveable contact assembly.
Reversing Moveable
Assembly Neutral
Pivot Slot
Figure 9.
Reversing switch moveable contact assembly.
Reversing Moveable
Button Contact
Reversing Segment

Cooper QD3 Specifications

General

Brand	Cooper
Model	QD3
Category	Controller
Language	English