Dynisco ATC770, Installation And Operation Manual

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2. Slide the instrument case into the cutout, being sure that it is right-side-up (terminal 1 at the
top). Attach the panel mounting hardware at diagonally opposite sides of the top and bottom of
the case, tightening the threaded rod until the case is secure against the panel.
3. Carefully slide the instrument back into its case, until the locking tabs have engaged. An audible
click will be heard as each tab engages.
4. Refer to the model number to determine the hardware and options included as part of your unit.
Please refer to Section 4.1 for the terminal assignments. Terminals are accessed by opening the
terminal covers from the side with the “OPEN” legend.
NOTE 1:
The ATC770 is equipped with screw terminals, and no connectors are necessary when wiring the
unit
NOTE 2:
When wiring the alarms, wire to the Common and NO (normally open) terminals to maintain a fail-
safe configuration. Remember to configure the software for failsafe operation.
Fail-safe denotes a situation where the alarms relay coils are activated in a no-alarm situation. As the
relay coil is energized, terminals that are normally open are closed and can cause completion of a
circuit when used as an interlock. Should the alarm threshold be exceeded, OR should power be
lost to the instrument the contacts will open, and the circuit will be broken. If the alarm is a latching
alarm, it will require an external reset signal to be activated again.
If the alarm is used to provide a contact to an alarm device (light, buzzer, etc.), when the threshold
is exceeded, wiring should be to the Common and NC (normally closed) terminals. Activation of the
relay coil will cause the contacts to open in a non-alarm situation, and on alarm, or if power is
interrupted to the instrument. If the alarm is a latching alarm, it will require an external reset signal
to be activated again.
NOTE 3: Relay outputs
The contact rating of all outputs is equal to 2A/240 VAC on resistive load.
• To avoid electrical shock, connect power line at the end of the wiring procedure.
• For power connections use No 16 AWG or larger wires rated for at least 75
°
C.
• Use copper conductors only.
NOTE 4: Power line
Before connecting the instrument to the power line, make sure that the line voltage corresponds to
the description on the identification label.
• To avoid electrical shock, connect power line at the end of the wiring procedure.
• For supply connections use No. 16 AWG or larger wires rated for at least 75
°
C
• Use copper conductors only