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IB01602078E
Instruction Booklet
Page
10
Effective: September 2011
40-400A (480/600Vac) ATC-300+ 3-Postion
Contactor Based Transfer Switch
5L. Source 2 3-Phase Voltage Unbalance
For a 3-phase wye source, this feature monitors phase volt-
age ratios. Voltage unbalance (%) is calculated as the dif-
ference between the maximum and minimum phase
voltage, divided by the minimum phase voltage. User-
selectable setpoints are available for dropout and pickup
unbalance settings (minimum 2% differential). Dropout is
adjustable from 5 to 20%. Pickup is adjustable from 3 to
(Dropout –2%). A setpoint for user-selectable time delay
from 10 to 30 seconds is provided. The factory default set-
points are: 5% dropout, 3% pickup, and 30 seconds time
delay. A user-selectable setpoint for enable and disable is
also provided.
When an unbalance condition is detected on Source 2, the
Unbalance Timer (TD UNBAL) starts timing. After TD
UNBAL times out, Source 2 is declared “failed”.
For a 3-phase delta source, this feature should be turned off
via the VOLT UNBAL setpoint.
6.
Test Operators
Generac ATSs are provided with a Test Pushbutton that
simulates a loss of the Source 1 power source as standard
(Feature 6B). All programmed time delays (TDNE, TDEN,
etc.) will be performed as part of the Test. Engine run time
of the Test is equal to the Plant Exerciser (Feature 23) pro-
grammed setpoint. All Tests are Failsafe protected.
6B. Test Pushbutton
Programmable setpoints include:
1. Load or No Load Testing, or Disabled
2. Engine run time equal to the plant exerciser
(Feature 23) setting
7.
Time Delay Emergency Fail (TDEF)
This feature provides a time delay that prevents a con-
nected Source 2 power source from being declared “Failed”
in order to override momentary generator fluctuations. If
the Source 2 power source remains in the failed state then,
0.5 seconds after the TDEF timer expires, the transfer
switch will proceed with the programmed sequence for
retransfer. This time delay is only implemented when the
Source 2 power source is a generator.
Adjustable 0 - 6 Seconds
8.
Time Delay Bypass Pushbutton
This feature provides a way (by pushing the Help and Step
pushbutton simultaneously) to bypass the TDNE (Feature 1)
and/or TDEN (Feature 2) time delays. The Time Delay
Bypass function, when activated by pushing the Help and
Step pushbutton simultaneously, will reduce any or all of
the programmed time delay to zero.
8C. Bypass TDEN
This feature provides one set of pushbuttons to bypass the
TDEN time delay.
8D. Bypass TDNE
This feature provides one set of pushbuttons to bypass the
TDNE time delay.
12. Power Source Annunciation
This feature provides LEDs to give switch position and
power source availability indications.
Switch Position
Provides LEDs to indicate the switch position
12C. Source 1 - Source Connected
This feature provides a green LED that, when lit, indicates
the load is connected to Source 1.
12D. Source 2 - Source Connected
This feature provides a red LED that, when lit, indicates the
load is connected to Source 2.
Power Source Availability
Provides LEDs to indicate if a power source is available.
LEDs may be integral or separate from the controller.
12G. Source 1 - Available
This feature provides a white LED that, when lit, indicates
Source 1 is available.
12H. Source 2 - Available
This feature provides an amber LED that, when lit, indi-
cates Source 2 is available.
14. Relay Auxiliary Contacts
14G. Source 1 Present:
Provides two (2) normally open and two
(2) normally closed contacts. The relay is energized when
Source 1 is available.
14H. Source 2 Present:
Provides two (2) normally open and two
(2) normally closed contacts. The relay is energized when
Source 2 is available.
15. Switch Position Indication Contact
This feature provides a contact that indicates if the power
switching device is in the “Open” or “Closed” position.
15E. Source 1 Position Indication Contact
This feature provides 1 dry form “C” contact that indicates
the position of the Source 1 power switching device.
15F. Source 2 Position Indication Contact
This feature provides 1 dry form “C” contact that indicates
the position of the Source 2 power switching device.
23.
Plant Exerciser (PE)
This feature provides a means for automatic testing of the
engine generator set or standby power system. All pro-
grammed time delays will be performed during plant exer-
ciser operations.
