P&B MR-REF, Technical Manual

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Page 22
MR-REF & MR-REF3 Technical Manual
Issue 3, November 2013
6.11. Stats Info.
If the Password is set to enabled, the password will be requested here to allow access to this menu.
This screen allows access to relays statistical
information.
To scroll through the available data use the up and
down pushbuttons on the frontplate of the relay.
In the left hand corner of the LCD a letter ‘R’ is shown,
this allows the reset (deleting) of individual statistical
values.
Statistical information available in this menu is as follows:
No. of Trips Number of Trips (total)
Acc Trp Current 1 Accumulated Trip Current for Ir1
Acc Trp Current 2 Accumulated Trip Current for Ir2
Acc Trp Current 3 Accumulated Trip Current for Ir3
6.12. Calibration Menu.
The calibration menu should not be entered unless it is absolutely necessary to do so.
Any inadvertent settings made here may compromise the accuracy of the unit and its ability to trip.
If the Password is set to enabled, the password will be requested here to allow read only access to the majority of
this menu. However the frequency setting can be changed and the relay outputs can be toggled.
The gain and offset values for each of the analogue
channels can be adjusted. Auto calibration routines
can also be performed.
Each unit is calibrated prior to dispatch and a signed
test report is issued. The user may however access
these settings if required and re-calibrate the device if
deemed necessary.
To achieve this, a unique password must be obtained from P&B protection relays. The serial number of the
unit will be required to do this.
In addition to the calibration of analogue inputs the Calibration Sub Menu provides some useful diagnostic tools.
After entering the password the Calibration Sub Menu will be displayed and allows access to the following settings:
Gain and Offsets for each analogue channel.
Typically a gain value is between 900 to 1200
Auto Iref Cal With injected Iref earth current channel can be calibrated
Reset Cal Factors Reset the calibration to default, gain=1024
Run Offset Cal Without any injected input, this sets all channels to 0.
Digital Inputs Check of the binary digital input status
O/P Relay Tests Output relays can be forced to changed state
Noise Check View the noise level readings per channel
System Frequency Corresponds the relay to the frequency of the measured system.
Feeder Type Changes and selects the function type of the relay.
Stats Info
Y
Top
No. of Trips
N
R 0
Calibration Menu
Y Top
Password=AAAAA
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