Operation; Automatic Mode; Monitor Mode; Control Inputs - Eaton ATC-300 Mode D'emploi

SECTION 5: OPERATION
5.1 General
This section specifically describes the operation and func-
tional use of the ATC-300 Controller. The practical use of
and operation within each category will be discussed. In this
section, it is assumed that prior sections of this manual were
reviewed and that the operator has a basic understanding of
the hardware.

5.2 Automatic Mode

The Automatic Mode of the ATC-300 Controller provides for
automatic transfer and re-transfer from Source to Source as
dictated by the features supplied and their programmed set-
point values. It provides a summary of the ATC-300 Control-
ler intelligence and supervisory circuits that constantly
monitor the condition of both the Source 1 and Source 2
power sources, thus providing the required intelligence for
transfer operations. These circuits, for example, automati-
cally initiate an immediate transfer of power when the power
fails or the voltage level drops below a preset value. Exactly
what the ATC-300 Controller will initiate in response to a
given system condition depends upon the combination of
standard and selected optional features.

5.3 Monitor Mode

Monitor Mode is a special operating mode in which the ATC-
300 Controller does not provide control for transfer opera-
tions. The ATC-300 will, however, continuously monitor
both Source 1 and Source 2 voltages and frequencies.
The ATC-300 will be in Monitor Mode when the "Monitor
Mode" control input is in the "Connected" state as described
in Section 5.4. While in the Monitor Mode of operation, the
ATC-300 LCD Display will display "ATS NOT IN AUTO-
MATIC".

5.4 Control Inputs

The ATC-300 has five individual input control signals. The
inputs are DC wetted with the unregulated DC supply and
appropriate current limiting to provide a nominal current of 10
mA per channel.
5.4.1 Control Input Descriptions
The Control Input "State" definitions are as follows.
Connected - When the input is shorted by an external contact
or connection.
Unconnected - When the input is NOT shorted by an external
contact or connection.
The Control Input operations are defined as follows.
Source 1 Closed
When this input is in the "Connected" state, it indicates to
the ATC-300 Controller that the Source 1 device is closed.
When this input is in the "Unconnected" state, it indicates to
the ATC-300 that the Source 1 device is open. This input is
typically wired to the Source 1 device auxiliary contact that is
closed when the Source 1 device is closed. The "Source 1
Closed" input is always enabled.
Source 2 Closed
When this input is in the "Connected" state, it indicates to
the ATC-300 Controller that the Source 2 device is closed.
When this input is in the "Unconnected" state, it indicates to
IB01602001T
ATC-300 Automatic
Transfer Switch
Controller
the ATC-300 that the Source 2 device is open. This input is
typically wired to the Source 2 device auxiliary contact that is
closed when the Source 2 device is closed. The Source 2
input is always enabled.
Lockout
When the "Lockout" input is in the "Unconnected" state, the
ATC-300 Controller will not permit an automatic transfer
operation. When the "Lockout" input is in the "Uncon-
nected" state, the LCD Display will be active continuously. It
will read "Lockout" on Line 2 of the LCD Display screen
immediately, regardless of any controller or switching device
operation. When the "Lockout" input is in the "Connected"
state and the Alarm is reset, the ATC-300 will permit auto-
matic transfer operation. This input is typically wired to the
normally closed Source 1 and Source 2 device alarm contact
that opens when one of the devices has tripped due to a fault
current. The "Lockout" input is selectable as enabled or dis-
abled via factory control only.
Go To Source 2
When the "Go to Source 2" input is in the "Connected" state,
the ATC-300 Controller is be in a normal, automatic operation
mode. When the "Go To Source 2" input is in the "Uncon-
nected" state, the ATC-300 controller will initiate a generator
start and then transfer to the Source 2 power source. The
ATC-300 will maintain the connection to Source 2 until the
input changes to the "Connected" state, upon which it will
initiate a re-transfer to the Source 1 power source. When the
"Go To Source 2" input is in the "Unconnected" state, the
LCD Display will be active continuously. Active time delays
will be constantly displayed on Line 1, with real-time remain-
ing countdown to zero status. It will constantly read "Go To
Source 2" on Line 2 of the LCD Display. This operation is
"failsafe". The "Go To Source 2" input is always enabled.
The "Go To Source 2" input does not have a user accessible
programmable setpoint for enable or disable.
Monitor Mode
When the "Monitor Mode" input is in the "Unconnected"
state, operation of the ATC-300 Controller will not be
effected. When the "Monitor Mode" input is in the "Con-
nected" state, the ATC-300 will monitor the Source 1 and
Source 2 voltages and frequencies but will not provide any
control capabilities. When the "Monitor Mode" input is in
the "Connected" state, the ATC-300 LCD Display will be
active continuously and will constantly read "ATS" on Line 1
and "NOT IN AUTOMATIC" on Line 2 of the LCD Display.
The "Monitor Mode" input is selectable as enabled or disabled
via factory control. The "Monitor Mode" input does not have
a user accessible programmable setpoint for enable or dis-
able. This is NOT a "failsafe" operation.
5.5 Output Relay
The primary control outputs of the ATC-300 Controller are
dry relay contacts. These relays are comprised of one latch-
ing "Form A" relay to provide the generator start contacts,
and four conventional coil "Form C" relays (two of which
implement only the Form A contact) necessary to complete
the electrical control function. Since the outputs were tested
per the UL 1008 Dielectric Test, the dielectric rating for each
output is a minimum of 1500 Vac. The output relays are
pulsed to eliminate error caused by software "races" between
Lockout and Source 1 or Source 2 Closed inputs.
The latched coil relay is UL/CSA rated at 5 A, 1/6 HP, 250
Vac. The DC rating is 5 A, 30 Vdc, with a 150 W maximum
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Instruction Booklet
Effective: January 2006 Page 15