Ampcontrol IPC1, Руководство пользователя

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IPC1 USER MANUAL ISSUE 9
-5-
The HV DC ‘Insulation Test’ is initiated when the
IPC Relay closes its relay output RL4 for 2
seconds. This applies 110VAC to the CCMC Cable
Connecting Module. A HV DC voltage is generated
in the CCMC Module, which applies a voltage
approaching the peak system voltage between each
phase and earth.
The IPC Relay measures the voltage on the line and
calculates the meg-ohm resistance to earth for each
phase. At the end of the test the result is stored in
the Event Log as
‘it -- . - M

’
If the resistance
value is above the preset threshold the MCR Relay
picks up allowing the outlet to be energised.
Additionally, if the result is equal to or below an
Alarm Level (typically 1.5 times the selected trip
level, see Table 1) the status message
‘Insulation
Alarm’
is displayed on the Status Page (level 0,
position 0). The alarm message is displayed until a
new EFLO Test is initiated or the
<ENT> key is
pressed while displaying the alarm message.
‘Insul.
Alm’
is also recorded in the Event Log.
Ins . TstT: Selection
M

Alarm Level
M

0.1 0.2
0.2 0.3
0.5 0.8
1.0 1.5
2.0 3
5.0 7.5
10 15
15 20
None None
Table 1
If the value is less than the preset trip level (0.1 M

to 15 M

) a trip occurs and is latched and saved in
a non-volatile memory. The “EF” LED on the
Remote Display Module is illuminated and the
open collector output on the relay is switched on to
provide remote monitoring if required. An
Insulation Trip shares the “EF” LED on the Remote
Display Module with an EFLO trip but has
dedicated trip messages on the Status Page. To reset
the relay following an insulation test fail trip,
operate the reset button.
At the completion of a test the leakage level for
each phase is retained in memory until the next test
is carried out. This can be viewed on the Remote
Display Module RDM (Level 3, Position 3).
If the ‘Insulation Test’ is not selected by either not
selecting CCMC or setting
‘Ins.TstT:’
value to
‘None’ then the MCR Relay closes at the
completion of a healthy EFLO Test.
The accuracy of the insulation test and expected
trip ranges are outlined in the table below. The
results from insulation test should only be used as a
guide to confirm that insulation remains above the
preset threshold. Insulation tests apart from the
generated insulation test via the IPC and CCMC
should be still carried out on a regular basis for
maintenance purposes.
Actual Fault Resistance (MΩ)
Trip Setting Minimum Maximum
0.5 0.4 0.6
1 0.8 1.2
2 1.6 2.4
5 4.0 6.4
Table 2
The values in the expected fault resistance range
represent ±20% of the nominal value with the
exception of the higher end of the 5MΩ range. Trip
setting values of 10MΩ and 15MΩ aren’t specified
above but are available for configuration within the
software. These trip settings of 10MΩ and 15MΩ
are not recommended for use by Ampcontrol.
Note:
That the start input must be held closed for the
duration of the test.
The recommended trip setting values to be utilised
for the insulation test trip settings are to be less than
5MΩ. To obtain optimum results the 2MΩ trip
setting is recommended.
3.2.3 Manual Insulation Test
A manual “Insulation Test” is provided as a
maintenance/fault finding tool. The manual test can
only be carried out when the load is not energized.
When this test is performed the MCR relay is
prevented from closing at the completion of a
healthy test.
Before a manual Insulation Test can be performed
the following conditions must apply:
1.
The Remote Display Module must be online
with the Insulation Test page being displayed.
This is located on the ‘
EARTH FAULT
INFORMATION
’ Page, level 3, position 2.
2. Pilot must be healthy (and any previous trips
reset).
3. EFLO function must not be tripped.
4. Insulation Test function must not be tripped.
5. Outlet must not be running.
6. Outlet must not be in the process of ‘closing’.
7.
Outlet must not be ‘Paused’
8.
The ‘Lock’ digital input must be closed.
When the above conditions are met the
<ENT> key
must be pressed and held (for the duration of the
test). After 3 seconds the EFLO test will
commence. If the test result is healthy the manual
insulation test is initiated. The test voltage is
applied to the outgoing feeder while ever the above