InsulGard System Installation and Start Up Guideline
25
InsulGard allows automated detection of phase shift between control power supplied to the device and
phase reference signal coming from phase A coupling capacitor connected to channel #1. If there is no coupling
capacitors a reference signal can be taken from a corresponding Potential Transformer or from any source with
known phase shift to HV system voltage
– see Appendix 7 of InsulGard User Manuals. Reference signal must not
exceed 5VAC RMS
– use appropriate divider to bring reference signal into preferable range of 0.1-1 VAC. This
operation should be performed one time considering that InsulGard power and system voltage connections have not
been changed during monitoring.
In asynchronous mode InsulGard power is not synchronous with the HV system power and continuous
synchronization signal must be used. It also can be taken from channel#1 coupling capacitor or from any other
synchronous voltage source mentioned above. Some changes must be done to the Sensor Interface Board for
asynchronous application. No phase shift measurements needed for that application. For typical applications 50Hz
+-10Hz
enter 275 degrees
shift.
Automated phase shift measurement can be done only from the InsulGard keypad
:
1. Press
Set
key to enter the setup mode. The password prompt should appear on the display as shown:
Enter Setup
Password: - - - 0
Enter the password
5421
by using
“←”
and
“→”
to move to different digits and
“↑”
and
“↓”
to change the values.
Then press
“Enter” key. Wait about 20 seconds for the display to change from dashed lines to “Set date” before
pressing any other key. If the wrong password is entered the dashed lines remain on the display until another key is
pressed. When InsulGard is in
Set
mode, the Set LED will be on.
2. Using
“←”
and
“→”
keys scroll to
Set Phase Shift
and Press
Enter:
Manual Input
Phase Shift
3. Use any arrow key to switch from Manual Input to
Auto Detect
mode:
Auto Detect
Phase Shift
4. Move
H%/Ref
switch at the bottom of the Sensor Interface Board to
Ref
position. Then press
Enter
to start
phase angle shift measurements. Display will update every 15 seconds.
Detecting Phase
-
5. Observe changing readings for 1-2 minutes and calculate average of the displayed values.
Note: Typically measured value deviates within the range of +/- 5
0
. Below are some hints that may help to identify
phase angle measurement problems:
Phase angle varies on more than +/-10
0
(low reference signal magnitude or high noise).
