SNV-EFI undergrounding fault detection

SNV-EFI Earth fault indicator

Type: surface mounted

Description

 SNV-EFI earth fault indicator, it Widely used in various ring cabinets, high/ Medium or low -voltage switch gear and cable branch box in power system, can accurately and reliably detect the fault section and fault type of power grid in the Low/medium voltage network. The use of cable type grounding fault indicator is an efficient way to check cable fault, and is an effective way to improve the operation level of distribution network and the efficiency of fault handling. The design uses electromagnetic induction, and single chip microcomputer control technology to make fault alarm with high accuracy and strong anti-interference ability.

Equipped with fault remote transmission port, suitable for distribution network automation;  Battery low power alarm indication; Low-power design, high-capacity lithium battery power supply, long battery life (more than 10 years); external structure using card or lock design, the whole machine is easy to load and unload.

Function character：

1) Intelligent detection of ground fault and through the corresponding LED on the display unit to indicate fault.

2）Display unit designed with button, it is convenient for reset or test.

3）The pulse width time of fault current can be set to prevent incorrect fault indication caused by surge current.

4）It can reset and detect the remote fault indication device remotely by Scada or press key.

5）It can provide switch volume for external devices through remote contact.

6）It can choose the reset time after fault happen (when purchase, it need to tell factory to set,default 8hours).

7）Remote fault indicating can be made by external lamp.

8）Earth fault alarm current,Multi-level can be settable through a DIP inside of the display nit(optional)

9）Low battery display and alarm test through press the “Test/reset” key by 3seconds.

10) Battery can be changeable conveniently.

Function description

1) Earth fault alarm indicating:  when the earth fault sensor detected an earth fault current, and the current is bigger than equal to or equal to the setting value, then the earth fault sensor send a signal to display unit  through electric cable. And the display unit will display the alarm signal, at same time, the earth fault LED will be blinking.

2) Battery low voltage alarm indicating: the display unit use the battery to supply power. When we press the “Test” button,3seconds time: If the battery voltage is lower than the Min. working voltage 2.5V, then the Battery Level Led will be blinking 5 times; If battery voltage is normal, then only blink 1 times.

4)Automatic time reset:  After the indicator alarm the fault, if there are without manual reset it, when the time reach our reset time setting, indicator will automatically reset.

5) Manual reset:  After the indicator alarm the fault, user can press the button “ reset/test” in a short time to reset it.

6)Automatic Low voltage reset: Through inputting AC110-240V power to the pin 10,11 on the PCB in the display unit, when fault indicating, at same the voltage powered off. when the voltage recover and power on again,  then indicator will be reset immediately via low voltage.

7) Out side AC110-240V power supply energy for display unit. It use the same as voltage of the “voltage reset” via pin 10,11.

8) Remote(Scada) reset/test: through short connect the pin 3,4, then indicator will be run the reset/test process, and Led will be blinking. *Connect the pin 3,4 by short time(1second), then it will be reset indicator. * connect the pin3,4 by a long time(3seconds), then it will be test indicator.

9)Remote indicating:  Through connect the pin 5,6 to the external lamp , then it will be indicate fault when any phase alarm fault. 

Technology parameter

Define and connect of terminal inside box.

Pin 1-2 : sensor connect

Pin 3-4 : Remote Reset/ test

Pin 5-6: External indicating LED

Pin 7-8: NC relay ,

Pin 7-9: NO relay

Pin 10-11:  power supply and voltage reset (AC110-240V)

 Operation description

1) Test:   Before installation, press the display panel’s “ reset/test “ button, 3 second. Then the indicator will go into the self- checking state:

--Battery Level voltage led flash 1 times, (if the battery low voltage, it flash 5 times);

-- Fault indicating led flash, after 10 second, display unit will recover back the normal state. Or shortly press the “ reset/test” button to finish the self-checking state.

2) Clean Alarm:  After fault indicating, when we solve the line or device problem, we can reset the indicator to Clean alarm as below three way:

1.  shortly press the “ reset/test” button to clean alarm,

2.  remote (scada) reset through connect Pin 3,4 by scada or key-switch control

3.  wait it automatically reset after reset time setting value.

4.  Voltage reset: when display unit voltage OFF , then voltage ON again.

Note: in order to use this Voltage reset feature, the 110-240Vac voltage must disappear when the fault occurs, i.e. it must be cut off by the MV circuit breaker that breaks the faulty line, otherwise the EFI will not operate voltage reset.

Working characteristics:

When the Earth line occurs fault current, and the fault current is above than the trip current level,and fault current is running a delay time above that “response time” level. Then indicator will be indicating fault. After a “reset time” EFI will be reset automatically.

 Installation

1) Dimension and installation:

   Display unit outside size: 152x90x56mm

Surface mounted on the wall or cabinet bolts M4. Hole distance position: 52mm x 135mm.

2)Earth fault sensor installation

Earth fault sensor need to round the 3 phases cable conductor together (if have phase N,then directly mounted on phase N cable). And tighten it with belt, and the cable grounding line must insert back the sensor, and tighten it avoid the loose and fall down. As below:

Fault indicator packing list

1. Display unit           1Pcs

2. Earth fault sensor with 5meters cable   1Pcs   

3. User manual         1Pcs

4. External Lamp(Optional)   1pcs

Purchase Tips:

 When purchase, please supply the following parameter.

1)Earth fault alarm current value: 10/25/50/75/100/125 /250 or other value. Default :50A

3) Automatically reset time.:  1H/2H/4H/8H/12H,  default :4H

4) Load fluctuation and escape pulse time setting (Response delay):

20ms/40ms/60ms/80ms/160ms Default :40ms