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| Printable
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| Power
Protection - Earth Monitoring Relays |
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A common
feature of all computers & other electronic equipment is
the sensitivity to supply Voltage fluctuations like Spikes etc.
These may damage the hardware or corrupt the data on software.
To ensure clean supply,computers are frequently installed on
dedicated clean circuits. They also have inbuilt suppression
& filtering
circuitry. These Filters leak the unwanted components of electric
supply to earth.
When large Number of computers are connected on same circuit,
the earthing is required to carry a significant amount of continuous
leakage current. Any break in earth connection will mean that
the isolated section will rise to potentially lethal voltage.
This will also render the filter circuits ineffective making
the computers prone to failures due to voltage spikes.
Therefore as recommended in IS 3043(Section 39.2.4.2), It is
necessary to provide a protective device to monitor the continuity
of the protective earth connection & provide means of automatic
disconnection in case of failure or at least give an audio alarm
to user.
The PROTIME’s Earth Monitoring Relay senses the rise in
voltage between earth & Neutral Conductor to detect the
integrity of the earthing connection. It is advisable to install
such relays at the UPS supply points & couple of Special
Features |
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Special
Features |
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Available
in door mounting (96 x96mm) channel mounting models. |
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Smart
design to fit on any standard mounting channel. |
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Choice
of screw less terminals |
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Total
wireless interiors |
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±
2% Accuracy |
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Test
& Auto/Manual Reset facility |
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Designed
for high reliability, as relay energizes only under fault conditions |
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Technical
Data |
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Supply Voltage
(control supply) |
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110V / 220V / 380V
/ 440V AC, 50Hz or 12V DC / 24V DC. |
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Permissible Supply
Variation |
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± 25% |
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Output Contacts |
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Two changeover contacts / One
change over with Buzzer |
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Switching duty |
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6A resistive at 24V DC or 240V
AC |
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Relay Status |
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De-energised in normal conditions. |
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Set Point(Range) |
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1- 10 V AC |
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Time delay (optional) |
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0.1-10 sec. Settable |
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Mode of operation |
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Over voltage |
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Reset |
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Automatic/Manual. |
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Setting Accuracy |
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± 5% of full scale. |
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Mounting |
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Any standard mounting channel. |
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Dimension |
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77mm(W) X 90mm(H) X 110mm(D).
For VR96-1 = 96mm(W) x 96mm(H) x 70mm(D) |
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Operation |
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The Relay senses
continuously voltage between earth & neutral terminal on
load side,. Since if earth gets disconnected , this voltage
will increase. The relay will give output for tripping or audio
alarm when such voltage rises above the limit set on the dial.
The time delay for relay output is optional feature. |
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Connection Details
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Note:- Design and specifications may change due to our continuous
developmental efforts.
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