Arrester monitor with remote indication

Transcription

1 Arrester monitor with remote indication Sensor 3EX5 060 Display 3EX5 062 Operating manual Order No.: b The copying, distribution and utilization of this document as well as the communication of its contents to others without expressed authorization is prohibited. Offenders will be held liable for the payment of damages. All rights reserved in the event of the grant of a patent, utility model or ornamental design registration. Siemens Aktiengesellschaft All rights reserved. Siemens AG 10/2004

2 Contents Contents 2 General 4 Description 4 Order code for sensor and display 4 Function description 4 Technical data 5 Transport and storage 5 Installation 6 Sensor 3EX Display 3EX Connecting lead 10 Order code for connecting lead 10 Connection to bus systems 11 Operation 12 Reading the surge counter 12 Reading the leakage current measuring device 13 Measurement output 14 Disposal arrester and arrester accessories 16 2 Siemens AG 10/2004

3 The manufacturer of this surge arrester Siemens AG Power Transmission and Distribution Group High Voltage Division has introduced and applies a quality system in accordance with DIN ISO 9001 / EN Quality systems: Model for quality assurance This system was first demonstrated in 1989 to the DQS (German Association for the Certification of Quality Systems). The electrical testing laboratories and the materials technology laboratories of the manufacturer have been certified since 1992 by the German Accreditation Body in accordance with DIN EN If you require further copies of the operating instructions, please order them from the appropriate Siemens office, indicating the title and order number shown on the title page. Published by: In case of request: Siemens AG Telephone exchange +49 / 30 / PTD H 4 Sales department: +49 / 30 / D Berlin Fax: +49 / 30 / mailto:arrester@siemens.de Subject to change. Note The equipment covered by these instructions should be installed and serviced only by competent personnel familiar with good safety practices. This instruction is written for such personnel and is not intended as a substitute for adequate training an experience in safe procedures. This information is intended for the correct installation of this product. Siemens has no control over the condition of the network, which can be greatly affected by the installation of a product. It is the responsibility of the user to chose the appropriate method of installation. Under no circumstance is Siemens liable for any direct or indirect damage caused by the use or misuse of this product. Siemens AG 10/2004 3

4 General Description The 3EX surge arrester monitor is a monitoring device with a remote indication unit consisting of a sensor and a display device for metal oxide surge arresters in both indoor and outdoor installations. The sensor is looped into the grounding line of the arrester to be monitored. The following functions are integrated:! Via an ma meter, display of the leakage current flowing permanently along the arrester (peak value measurement)! Surge counter (electromechanical counter)! Measurement output for oscillographic display of the arrester leakage current. The 3EX5 060 sensor basically consists of the pickups for leakage current measurement and the surge counters which are resin-encapsulated. The resin casting simultaneously serves as the housing. The 3EX6 062 display unit contains the leakage current display (ma meter) and the surge counter. They are accommodated in a stainless steel enclosure with a front panel made of glass to allow them to be read. A socket is provided at the rear of the enclosure (measurement output). The sensor is connected to the display unit via a special multicore screened cable (included) measuring no more than 200 m. Order code for sensor and display Type Description Remarks 3EX5 060 Sensor For display 3EX EX5 062 Display With measuring socket Function description 3EX EX Toroidal core transformer 2 Protective spark gap 3 Resistor 4 Primary conductor 5 Evaluation electronics Fig. 1. Block diagram 6 Connecting lead 7 Leakage current display 8 Leakage current measuring socket e.g. for osciloscope (Amphenol C16-1) 9 Counter Under normal operation the arrester leakage current flows to ground via the primary conductor and the resistor. The evaluation circuitry displays its peak value on the leakage current measurement unit. When the arrester operates, the discharge current sent along the primary conductor induces an impulse voltage in the secondary winding which in turn increments the counter one step. Depending on the measurement principle used, the sensitivity of response of the counter will depend on the virtual steepness and the duration of the discharge current. 4 Siemens AG 10/2004

5 At the resistor the discharge current causes such a large drop in voltage that the protective spark gap responds. The voltage drop which occurs by this time does in fact take place before the peak in the arrester discharge voltage and thus does not affect its magnitude. The voltage drop then falls to negligibly low values. Technical data! Leakage current display (3EX5 062): ma meter with non-linear scale 0 ma 20 ma ± 20 %! Surge counter (3EX5 062): Sensitivity Current waveform 4/10 µs, 8/20 µs 1000 A Currenmt waveform 30/60 µs 200 A Current waveform, rectangular wave discharge current 100 A! Measurement output for e.g. oscilloscope (3EX5 062 :1 :2): Transformation ratio 470 mv/ma.. R ein 1 MΩ! Measurement output for peak value measurement 3EX5 060(:4 :E)! Switching contact (NC) 3EX5 060 (:5 :6) On request Switching voltage: 250 V AC/DC Switching current: 1 A Switching capacity: DC 30 W / AC 60 VA Bounce time: approx. 1 ms. Contact time: ms! Ambient temperature C Transport and storage The operation indicators are supplied packed in cardboard boxes. They must be unpacked if they are to be stored in humid conditions (such as in the tropics, for example). Siemens AG 10/2004 5

6 Installation Warning Before any work starts:! switch off and isolate! secure against reclosing! verify that equipment is dead! earth and short circuit the equipment! cover or fence off nearby live parts Death, severe injury and considerable damage to property and environmental damage may result if the safety instructions are not followed.! Confirm that these safety measures have been carried out. Sensor 3EX5 060 It is absolutely essential (for the proper functioning of the sensor) for the arrester to be installed on insulating mountings. The sensor is installed on the ground connection of the arrester. Be sure not to exceed the permitted tightening torques for the screws:! M max = 30 Nm ± 1 Nm. The ground connection of the sensor is connected to system ground - the metal frame of the arrester, for example. A copper wire 35 mm² in cross-section and not longer than 2 m is recommended for this purpose. The sensor is connected to the display by means of a special lead (see Fig. 7.). When installing this lead make sure that there is adequate clearance to live parts (at least 30 mm). Fig. 2. Installation 3EX Siemens AG 10/2004

7 Fig. 3. View from below If the 3EX5 060 sensor is installed in series with a tell-tale spark gap (a 3EX6 040, for example) the sequence of the devices is important: Connection for monitoring devices " Tell-tale spark gap " Sensor " System ground (e.g. tower base) Fig. 4. Installation sequence for outdoor arresters Siemens AG 10/2004 7

8 a 1 Enclosure bushing for connecting monitoring devices 2 Post insulators for insulated installation of tell-tale spark gap 3 Tell-tale spark gap 3EX Operation sensor 3EX System ground Fig. 5. a: Installation sequence for encapsulated arresters without a tell-tale spark gap b: Installation sequence for encapsulated arresters with a 3EX6 040 tell-tale spark gap b Note The wiring run between the connection for monitoring devices and the ground connection should be kept as short as possible. 8 Siemens AG 10/2004

9 Display 3EX5 062 The display can be installed at distances of up to 200 m (maximum length of connecting lead). Greater distances are however possible on request. The display is connected to the sensor by means of a special lead. The display enclosure must be installed so that it is grounded effectively. Be sure not to exceed the permitted tightening torques for the screws:! M max = 30 Nm ± 1 Nm. Fig. 6. Installation of 3EX5 062 Warning To ensure proper shock-hazard protection the housing of the 3EX5 062 display must be grounded effectively. Siemens AG 10/2004 9

10 Connecting lead Fig. 7. Connecting lead between sensor and display Ready-assembled connecting leads are available. If so required, you can also make up the leads yourself. For each lead you will need a plug and an angle socket, C16 series, six-pole, manufactured by Amphenol. The plugs and sockets can also be ordered as pairs from Siemens. Order code for connecting lead Type Description Remarks 3EX Plug and socket for connecting lead For customer assembly 3EX D Connecting lead, 3 m Pre-assembled 3EX G Connecting lead, 6 m Pre-assembled 3EX A Connecting lead, 10 m Pre-assembled 3EX C Connecting lead, 12 m Pre-assembled 3EX E Connecting lead, 14 m Pre-assembled 3EX G Connecting lead, 16 m Pre-assembled 3EX J Connecting lead, 18 m Pre-assembled 3EX A Connecting lead, 20 m Pre-assembled 3EX C Connecting lead, 22 m Pre-assembled 3EX E Connecting lead, 24 m Pre-assembled 3EX G Connecting lead, 26 m Pre-assembled 3EX J Connecting lead, 28 m Pre-assembled 3EX A Connecting lead, 30 m Pre-assembled The following is used as lead: PVC-C-LIYCY, mm². The connection between the plug and socket is shown in the following diagram: Fig. 8. Connecting lead diagram 10 Siemens AG 10/2004

11 Connection to bus systems The outputs of the 3EX5 060 sensor can be connected to the interface cards of the bus systems directly or via commercially available transformers (4-20 ma current loop, for example) (R in 1 MΩ). In the event of arrester operation, an internal protective circuit in the measurement outputs limits the voltage pulse which occurs to a value of û imp 350 V. Warning Due to the voltage surges which can occur during arrester operation you should ensure that adequate suppressor circuitry is installed in the inputs of transformers or interface cards. Siemens AG 10/

12 Operation Use of the measurement output and reading the leakage current measurement device is only possible when the system is in operation - in other words, when the system is not isolated. Warning Non-compliance of safety hints can course death or serious injures. Always maintain a safe distance from live parts! Use binoculars for reading measuring instruments and indicators, if necessary. Reading the surge counter Fig. 9. Surge counter The surge counter displays surge arrester operation events which occur when threshold values are exceeded. Note Due to routine inspection and testing having been carried out, the arrester monitor will already display a value greater than 0 when shipped. 12 Siemens AG 10/2004

13 Reading the leakage current measuring device Fig. 10. Leakage current measuring device Under normal circumstances the pointer deflection should not exceed 2/3 of the range on the scale. If the pointer is in the range marked >20, measurement should be repeated at a later time since the leakage current through the arrester could be falsified by foreign conductive deposits on the surface of the arrester housing. In the same way, increased leakage currents can occur immediately after a reading due to a temperature increase in the active part of the arrester; this problem would not however occur with shorter periods of time. If measurements subsequently repeated still yield the same results, you should contact the manufacturer of the arrester. Siemens AG 10/

14 Measurement output Fig. 11. Measurement output The rear of the display unit is provided with a C16-1 socket (Amphenol) as a measurement output for the leakage current time curve. The transformation ratio at the measurement output is ü = 470 mv/ma. The input resistance of the connected measuring device (an oscilloscope, for example) must have a value of R in 1 MΩ. In the event of arrester operation, an internal protective circuit in the measurement outputs limits the voltage pulse which occurs to a value of û imp 350 V. When the system is not in use, the cover cap must be replaced to protect the socket from environmental influences. The cap is permanently attached to the socket by a plastic chain. As a simple way of connecting an oscilloscope, a special lead (order no.: 3EX ) for connecting the measurement output and the oscilloscope is available (not included in the scope of supply). 14 Siemens AG 10/2004

15 . Fig. 12. Lead 3EX for connecting measurement output and oscilloscope Siemens AG 10/

16 Disposal arrester and arrester accessories Surge arresters and the accessories are an environmentally compatible product. In disposal, priority must be given to reuse of the materials. Environmentally acceptable disposal of the surge arresters and the accessories is possible in line with current legislation. The following materials have been used to make up the device: Steel, copper, aluminium, PTFE, cast resin or cast-resin-impregnated fabric, glass-fibre-reinforced plastics, polyurethane, rubbers for sealing, ceramics, electronic components and silicon rubber (VMQ), ceramics (porcelain, metal oxide). The device can be recycled as mixed scrap, or, if it is dismantled as far as possible, in a more environmentally acceptable way as sorted scrap with a mixed-scrap residual portion. The arrester resistors of metal oxide (MO) should be disposed of as industrial waste similar to domestic garbage (not as building rubble). In as-supplied-by-siemens state, the device incorporates no hazardous substances in the sense of the pertinent regulations in Germany. If the device is to be operated outside Germany, the locally applicable laws and regulations must be followed. Local customer support offices will be able to answer any questions concerning disposal :01 16 Siemens AG 10/2004