Utility Relay Company AC-PRO-II, Instruction Manual

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AC-PRO-II
®
Instruction Manual www.utilityrelay.com
Page 44
For 1-Amp and 0.5-Amp secondary CTs:
+ /- 2% for currents between 20% and 150% of CT Rating
For CTs with secondary below 0.5A:
+ /- 2% for currents between 50% and 150% of CT Rating
Voltage accuracy:
+/- 1.5% for 80V and greater, +/- 1.2V for 0 – 80V.
Power accuracy (Instantaneous values)
+/- 5% for currents between 10% and 150% of CT rating
Energy calculations: Refer to Section 13.0.
If an internal error occurs in the AC-PRO-II, the OK LED will
not be lit and the screen below will appear.
Figure 20.1: Internal Error Screen
If this screen appears and persists, please contact Utility
Relay Company.
If configured in user settings, the alarm relay will operate for
this condition. The “Exit” button is available and allows
bypassing this screen for temporary menu navigation. If the
condition is still present, this screen will re-appear the next
time the display is turned on.
If the AC-PRO-II detects an open circuit at the actuator
terminals, the OK led will not be ON and and the following
screen will appear, indicating an actuator open circuit
condition, in which case the trip unit will not trip the breaker.
repair the actuator connection.
Figure 20.2: Actuator Open screen
If configured in user settings, the alarm relay will operate for
this condition.
The “Exit” button is available and allows bypassing this
screen for temporary menu navigation. If the condition is still
present, this screen will appear the next time the display is
turned on.
20.3 Alarm Screens
If configured in user settings, the alarm relay will operate
when a trip, OV, or UV alarm occurs and the following
screen(s) will appear.
Figure 20.3: Trip Alarm Screen
Figure 20.4: OverVoltage Alarm Screen
Figure 20.5: UnderVoltage Alarm Screen
Figure 20.6: Clear Alarms Screen
Pressing the “View” button will show the trip history
information. Pressing the “Clear” button will show the clear
alarm screen. Pressing “Exit” will temporarily bypass this
screen for temporary menu navigation. If the condition is still
present, this screen will appear the next time the display is
turned on.
20.4 Un-Calibrated
If the following screen appears, do not place the trip unit in
service. Please contact URC.
Figure 20.7: Un-Calibrated Screen
18.5 Current Metering Accuracy
19.0 Voltage & Power Calculations
20.0 Error and Alarms
20.1 Internal Error
20.2 Actuator Open Circuit