IB140042EN
For more information visit: www.eaton.com
Instructional Booklet
Effective: May 2015
Page
13
ATC-300/900 Breaker Based Transfer Switch
3.5 Features
A variety of standard and optional features are available for Eaton
ATSs.
All features or combinations of features may not be avail-
able on specific ATSs
. All features and/or accessories are Under-
writers Laboratories (UL) listed unless noted.
3.5.1 Standard Features
The following is a list of the standard features for the ATC-300+
and the ATC-900 Controlled ATS. There are other options avail-
able, see the controller IB supplied. Customer Order Engineering
(COE) may also be applied to the switch, see the drawings for
those options.
1.
Time Delay Normal to Emergency (TDNE)
This feature provides a time delay when transferring from the
Source 1 to the Source 2 power source. Timing begins
when Source 2 becomes available. It permits controlled
transfer of the load circuit to Source 2.
2.
Time Delay on Engine Starting (TDES)
This feature provides a time delay of the signal to initiate the
engine/generator start cycle in order to override momentary
power outages or voltage fluctuations of Source 1.
3.
Time Delay Emergency to Normal (TDEN)
This feature provides a time delay of the re-transfer opera-
tion to permit stabilization of Source 1. Timing begins when
Source 1 becomes available. If Source 2 fails during timing,
then re-transfer is immediate overriding the time delay.
4.
Time Delay for Engine Cool-down (TDEC)
This feature provides a time delay of the signal to initiate the
engine/generator stop cycle after the re-transfer operation.
This allows the engine/generator to cool down by running
unloaded. Timing begins on completion of the re-transfer
cycle.
5,
Source 2 Monitoring and Protection
This feature provides monitoring and protection based on the
Source 2 voltage and/or frequency setpoints. All feature 5
functions are “failsafe” operations.
5B, 26B. Phase Undervoltage and Underfrequency Protection
Adjustable Undervoltage & Underfrequency
5C, 26C. Phase Overvoltage/Overfrequency
Adjustable Overvoltage & Overfrequency
5D, 26D. Phase Undervoltage
Adjustable Undervoltage
5E, 26E. Phase Overvoltage
Adjustable Overvoltage
5F, 26F. 3-Phase Undervoltage
Adjustable Undervoltage
5G, 26G. 3-Phase Overvoltage
Adjustable Overvoltage
5H. Phase Reversal
For a 3-phase wye source, this feature monitors the phase
sequence of the sources. If a source does not have the same
ABC or CBA sequence as the setpoint value, that source will
be considered “Unavailable.
For a 3-phase delta source, this feature should be turned off
via the PHASE REV setpoint.
5J. 3-Phase Undervoltage and Underfrequency Protection
Adjustable Undervoltage:
Dropout: 50 - 97% of nominal
Pickup: (D2%) to 99% of nominal
5K.3-Phase Overvoltage/Overfrequency
Adjustable Overvoltage:
Dropout: 105 - 120% of nominal
Pickup: 103% to (Dropout –2%) of nominal
Adjustable Overfrequency:
Dropout: 103 - 110% of nominal
Pickup: 101% to (Dropout -1Hz) of nominal
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 differ-
ence between the maximum and minimum phase voltage,
divided by the minimum phase voltage. User-selectable set-
points are available for dropout and pickup unbalance set-
tings (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 sec-
onds is provided. The factory default setpoints 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
Eaton ATSs are provided with a Test Pushbutton that simu-
lates a loss of the Source 1 power source as standard (Fea-
ture 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) programmed
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 setting
