Graco 562870, Instructions Manual

Page: 11 / 28

General Feature Information
313903B 11
General Feature Information
Tachometer
Displays actual engine/compressor shaft speed (RPM).
A flashing asterisk indicates the tachometer is enabled.
A second LCD line displays the normal target operating
speed.
An ON/OFF indication displays to indicate when alarm
monitoring is active.
It is possible to override the active alarms when the
tachometer is enabled and drive mechanism is operat-
ing a minimal speed, by pressing the
RST/CLR button
until the machine accelerates to 50% of it’s normal oper-
ating speed. At that point, the alarm override ceases,
allowing proportional alarmed startup of the equipment.
Enabled alarms stay active through all ranges of input
rpm until they are manually reset after the machine has
decelerated from 50% of its normal operating speed.
NOTE: When the alarm override is active, a letter “T”
and the word “OFF” will be displayed on the LCD.
When the RST/CLR button is pushed to reset Sentinel
II, the display resets back to 0 (zero). However, if the dis-
play is in the totalized mode (identified by the letter “T”)
pressing
RST/CLR resets the totals back to the last
stored value. Care should be taken when resetting a
fault to ensure that the display is not in the totalized
mode. Resetting the fault will also reset the total accu-
mulated usage.
Zone Enable/Disable
Zones are enabled during programming. A zone may be
disabled initially by programming the zone “OFF” or by
temporarily placing an enabled zone in “BYPASS” mode
(Terminals 29, 30, 31 and 32).
Closing the contacts for “ZONE BYPASS” disables a
zone from any fault time-outs. The zone display shows
the word “BYPASS” to indicate this condition.
When the bypass has been removed, active monitoring
of the zone continues. If the alarm is enabled, the alarm
time-out will restart.
Fault Relay
There are three fault relays. One is used as a Power
Monitor and two are used as Zone Fault relays.
The Power Monitor Relay is a single-pole, double-throw
relay with Form C contacts. It energizes approximately 5
seconds after power is applied and stays energized as
long as power is available to the monitor. When power is
removed from the system, the relay deenergizes imme-
diately.
Zone Fault Relays are enabled during programming.
Each Zone Fault Relay is a double-pole, double-throw
relay with two Form C contacts that change state when
their associated zone goes into fault. The Zone Fault
Relay may be programmed to either pick or drop when a
fault is detected, allowing for fail-safe operating if
desired.
A system fault TTL output is also available to annunciate
faults. It is linked with programming for relay energiza-
tion settings.
Resetting Faults
Faults may be reset in several ways:
• Manually reset at the monitor by pressing the
RST/CLR button.
• Using the “Safety Set” target (see Safety Set,
page 8).
• Electrically by closing the remote reset contacts.
• Serial Port commands (see Serial Communica-
tion, page 9).