Monitor Tra Messko MTeC_EPT202_en[1]

Temperature Monitoring and Intelligent Cooling Control for Transformers

MTeC®-EPT202www.messko.de

Messko

EPT 202 ENGL.2008 Einzelseiten:Layout 1 03.02.2009 11:37 Uhr Seite 1

MTeC®-EPT202 - A Multi-Talent in Action

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EPT202 IMMTeC®

POWER

RxD

TxD

ERROR

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POWERWTI 1

WTI 2

WTI 3

ALARM II

TRIP II

OL1 MAX

OL1 MIN

OL2 MAX

OL2 MIN

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MTeC® EPT202OL/CT

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POWER S1

ALARM S2

TRIP S3

ERROR S4

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EPT202

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Sensor data from the transformer Direct attachment or installation in switching cabinet Cabinet Switching / Control room

Switching signalAlarm/trip

Fan control

Analog outputs(temperature)

Digital output

Fiber optic conductor

Ethernet

Control system protocols(DNP3,0; others)

RS485/RS232

Temperature (oil)

Secondary current winding 1

Temperature (ambient)

Oil level

Temperature

Moisture (oil,...)

Switching signals

Other signals

SPI BUS

SPI BUS

Switching signalAlarm/trip

Analog outputs(temperature/oil level)

Secondary current winding 2/3


All in one deviceDepending on the particular region, many different demands are made on power transformer cooling monitoring devices. Withheavily loaded transformers, the fans (groups of fans) should be activated early enough. This can significantly lengthen the powertransformer life-time – which is calculated by the EPT202. Intelligent control also ensures that the fan groups alternate with eachother and run evenly. Keyword: fan running alternation. Other transformers may sometimes never reach the critical temperaturefor activation of the fans. The EPT202 offers the possibility to activate the cooling systems periodically to avoid e.g. bearing failuresdue to dirt ingression. EPT202 stands for a second-generation Electronic Pointer Thermometer. This means that a decade ofexperience has been combined in this device. For example, it offers memory for recording all oil and winding temperature(s), aprotocol function and various interfaces as well as extensive visualization software. And finally, different designs are available forcustomer-specific installation – at prices which are considerably less than having to buy expensive monitoring systems. The modular design of the EPT202 makes it easy to expand. For example, if oil levels or several winding temperatures are to beintegrated, an add-on module is simply plugged in. A proven concept which has already convinced many energy providers all overthe world

The primary functions

- Measurement/indication of the oil temperature and up to 3 winding temperatures- Oil level indication of the conservator (e.g., tank and on-load tap-changer)- Indication of the ambient temperature- Remaining lifespan calculation as per IEC and ANSI standards- "Drag hands" function for min. and max. values- Internal data storage for up to 32,000 data records- Data readout and storage in Excel format- Intelligent (based on type of cooling and load) cooling stage activation; parameterization of the individual cooling

stages possible- Cyclic and load-dependent cooling stage activation- Fan running alternation to equalize operation time of the fans- Protocol function- Device self-monitoring- Information visible on status, alarm, trip and state of the fans via device LEDs- Analog and digital outputs for remote transmission of the measured values; DNP3.0 protocol via IM module- IM module can be used as a stand-alone device to connect additional sensors to the network protocols. - Diverse installation and combination options

EPT202 basic module + EPT202 OL/CT expansion module


Parameters for the calculation of the “thermal image“ of a transformer such as gradient or winding exponentchange when cooling stages are turned on or turned off. These parameters can be set on the EPT202 for different cooling stages.The parameters of the current cooling stage are used for the calculation.

The device uses algorithms to calculate the lifetime consumption for the transformer's insulation system.Either the ANSI or IEC standard applies. Both algorithms are a function of the hotspot temperature.The result is then shown as a percentage based on the expected lifespan.

Indication of the temperature peak values with the EPT202 software Indication of the lifespan consumption

A hot topic: temperature monitoringThe aging process of a transformer's insulation systemdepends mainly on the temperature of the winding.The EPT202 calculates this from the oil temperatureand the specified load current as per IEC 60076-7or ANSI IEEE standard C.57.91.Calculation as per IEC 60076-7

Calculation as per ANSI IEEE standard C57.91

with ΘHotspot(t) : Hotspot temperature at time tΘTopOil : Current top-oil temperatureH : Hotspot factor (only for IEC standard)gr : Gradient of the average winding temperature to average oil temperature

for rated current (only for IEC standard)∆ΘH,R : Gradient of the hotspot temperature to the top-oil temperature for rated

current (only for ANSI standard)K : Load factor (actual current/nominal current)y : Winding exponent (only for IEC standard)m : Exponent for calculation of the current hotspot temperature

(only for ANSI standard)τ : Time constant of the transformer oil

98 1,0 30 years 0,282104 2,0 15 years 0,536110 4,0 7,5 years 1,0 30 years116 8,0 3,75 years 1,83 16,4 years122 16,0 1,875 years 3,29 9,12 years128 32,0 0,9375 years 5,8 5,175 years

Aging rate ofthe insulationsystems for non-upgraded paper*

Expectedlifespan for non-upgraded paper*

Aging rate ofthe insulationsystem forupgraded paper*

Expectedlifespan for non-upgraded paper*

* Upgraded paper: Pulp-based paper which has been chemically modified to reduce thedecomposition rate. All calculations for an average transformer lifespan of 30 years: Source:ICE 60076-7, 2007.

ΘHotspot (t)

in °C

ΘHotspot(t)=ΘTopOil + H x gr x K y x [1-et ]τ

[1-e ]ΘHotspot(t)=ΘTopOil + ∆ΘH,R x K2m x τt


Cool calculation: Cooling system controlThe EPT202 uses the oil and winding temperatures to control various cooling units (groups of fans or pumps). The natural coolingof the transformer (usually 0NAN) is always present as the basic stage.0 = Interior cooling medium: oil, with a flashpoint > 300° CN = Natural oil flow through the cooling system and the windingsA = Exterior cooling medium: airN = Natural flow(Classification as per IEC 60076-7 and IEEE C57.12.00-2006)This cooling stage does not have a cooling device which is controlled by the EPT202.

There are different ways to activate the cooling stages:

Activation of the cooling stages via switching points for the oil or winding temperatureIn addition, four additional cooling stages (e.g., 0NAF or 0FAF) can be switched through. This is done with relay contacts. Thesecan also be used alternately for warnings. Switching point, hysteresis and delay time can be set for each stage. Contacts whichare not used can be blanked out. Activation of the cooling stages can be done via oil or winding temperatures (e.g. turn on coolingstage ONAF when an oil temperature of 60°C is exceeded). The temperature at which activation or switchoff is to take place canbe set as desired. The "manual on" command means that the cooling stage is always on.

Fan running alternation (load cycle mode)Fan running alternation loads the individual fans uniformly. This savesmaintenance costs in the end since wear and tear are distributed over allthe fans. Fan running alternation can be set on the EPT202. After this time expires,the relays of the assigned switching contacts are switched over insuccession. Load alternation switching is usually used for a transformerwhich is equipped with several rows of fans.

Activation of the cooling stages depending on the loadIf a transformer fails during parallel operation, this may quicklycause a great increase in the load of the other transformer. Due tothe applications for which they are used, machine transformers mustalso be able to operate briefly under an overload. This is the reasona load depending activation limit value can be set on the EPT202.This corresponds to the transformer load as a percentage. If thisvalue is exceeded, the cooling stages are activated. However, thecooling system control via the temperature limit values is always stillthere in the background.

Cyclic cooling stage activationThe cooling systems are very rarely activated for transformers which are operated under a low load. To keep the fans fromstanding still for long periods of time, cyclic activation is useful for these transformers. Cyclic activation of the fans can also behelpful during the winter months. That is why three parameters can be set on the EPT202 for every cooling stage: switchondelay (i.e., the time which must expire before the first activation), run time and the interval after which the cooling stages are tobe switched on again.

Setting of cooling stage activation

Transformer fan groups


Play it safeA monitoring device like the EPT202 must record the data reliably. The EPT202 has a self-monitoring function to ensure that it isfunctioning correctly. If, for example, the power fails or an analog output is open, this is reported via an ERROR relay. Theswitching of this relay can be parameterized. A message concerning the power should be omitted, for example, when thetransformer frequently switches between its own power and the network power.

The EPT202 offers a function to test the switching contacts. The software permits you to select whether alarm or trip messagesare to be sent. All device functions continue to run in the background.

Parameterization made easyAll device functions can be accessed with the menu of thedevice's software. The cursor keys on the right side of the de-vice make it easy to navigate through the menu levels. Ente-ring or changing a parameter is child's play. Everything can also be set quickly and easily via the visualiza-tion software. For this, the EPT202 is connected with a PC orLaptop via the USB connection on the front. A USB driver isinstalled for this purpose. Parameterization via the software is available in 4 languages(English, German, French and Spanish).

The EPT202 offers an offline function. This means that youcan already begin parameterization without a connection tothe EPT202. When this function is set up, the data are easilyuploaded later on.

Parameterization is very easy with the Easy Set function. Pa-rameter records corresponding to the IEC 60076-7 standardare suggested for the cooling stages. It is easy to use thesesuggestions and conclude the parameterization.

And everything is savedThe EPT202 has an internal data memory for up to 32,000data records. The time interval after which the data aresaved can be set as desired. A data record is naturally alsosaved after every event when, for example, an alarm orswitching contact was activated.The data memory can be read out with the visualizationsoftware. All data are stored in Excel format and can thenbe edited as desired.

EPT202 data logger

EPT202 Easy Set function


Communication that catches onThe standard EPT202 is equipped with one analogoutput for the oil temperature and one for thewinding temperature for different measuring ranges.These outputs ensure reliable transmission of thevalues to the control room. The additional OL/CTmodule is equipped with more analog outputs forwinding temperatures and oil levels.

The EPT202 is equipped with a USB interface forparameterization and reading the data. The RS485interface can be used for continuous communicationwith the visualization software.

The modules communicate with one another via theSPI bus. For example, parameterization of the OL/CTmodule is simple via the basic module.

A module for flexible connection to thecontrol technologyThe EPT202IM communication module convertssimple analog and digital signals into protocolswhich can be used by the control technology. Itstores the values of the other EPT202 modules in adual-port RAM. In addition, values of otherconnected sensors can also be stored.

On the output side, the IM module offers interfacessuch as RS232 and RS485. An RJ45 socket permitsdata transmission via modem or Ethernet. As anoption, data can also be transmitted via fiber opticconductors. This is useful when strong electricalinterference is to be expected.

The DNP3.0 protocol can be implemented with theIM module, for example. Messko offers the DeviceProfile (a standard form with the supported dataobjects) for this purpose and the overview of thedata points. Cyclic or event-controlled events canthen be sent to the control system via the DNP3.0.Well-known control technology protocols can alsobe implemented on request.

Finally, the IM module can also be used as anindependent device without the EPT202 basicmodule. This can be used to convert analog signals(e.g., "oil temperature") or binary signals (e.g., "oillevel too low") into control technology protocols.

EPT202 installation

EPT202 IM module


Technical data of the EPT202Protective housing

Installation on mounting rail Aluminum housing, can be snapped onto mounting rail as per DIN EN60715 TH 35-7.5 and TH 35-15,

protection rating IP 00 as per IEC 60529, weight approx. 1.2 kg

19" module rack 19" slide-in housing as per DIN 41494, part 5; 223 mm x 133 mm x 178 mm (W x H x D) forinstallation in 19" cabinet system, protection rating IP 00 as per IEC 60529, weight approx. 1.5 kg

Installation in control panel Aluminum housing 270 mm x 200 mm x 133 mm (W x H x D) for panel cutout 236 mm x 142 mm(W x H), protection rating IP 00 as per IEC 60529, weight approx. 1.5 kg

Installation in TAPMOTION® 19" slide-in housing as per DIN 41494, part 5; 483 mm x 133 mm x 178 mm (W x H x D), protection ED motor drive from MR rating IP 00 as per IEC 60529, weight approx. 2.5 kg

Temperature rangeOperation -25° C...+70° C (-13°F…+158°F)Storage -30° C...+85° C (-22°F…+185°F)

Operator control elements, indication, terminalsOperator control elements 5 function keys with tactile pressure point Indication Monochrome display, black characters and white background or white characters and blue back

ground, 128 x 64 dots

One device with many facesThere are many ways to mount the EPT202 with its add-on modules.

- Mounting on mounting rail: The EPT202 can be installed in an aluminumhousing and snapped onto a mounting rail as per DIN EN60715.

- Installation in a control panel: Similarly an aluminum housing with afixed panel cutout for direct installation in the switching cabinet.

- 19" slide-in housing as per DIN 41494, part 5

Installation in the TAPMOTION® ED motor drive from MR. A 19" slide-inhousing is also used here but with double the width.

If the EPT202 is to be mounted on the transformer, it can be protectedfrom the elements (i.e., weather) with an NEMA 4 or IP65 housing.

Other things you should knowSpecial solutions already exist now for individual power providers. Forexample, Messko developed a special version for a large South Africancustomer. From South Africa to Canada, from Algeria to Thailand – thereliable EPT202 devices are in operation all over the world. And theirnumber is constantly growing ...

When you buy a Messko device, you can be sure that it exceeds thedemands of existing testing standards. Naturally, all devices of the EPT202family have been tested for electrical safety, electro-magnetic compatibilityand resistance to temperature and climatic conditions in accordance withthe applicable standards. Each device is delivered with a test certificate. This certificate lists all teststhat the device has passed, together with the important device data. Qualitythat you expect from Messko.

EPT202 mounted in a control panel


1 green LED for "Power" indication1 yellow LED for "Alarm" switching contact1 red LED for "TRIP" switching contact1 red LED for "ERROR" switching contact4 yellow LEDs for switching contacts S1, S2, S3 and S4

1 green LED for "Power" indication1 yellow LED for "Alarm II" switching contact1 red LED for "TRIP" switching contact3 yellow LEDs for switching contacts WTI 1, WTI 2 and WTI 3 (winding temperature)4 yellow LEDs for switching contacts 0L1 MAX, 0L1 MIN, 0L2 MAX, 0L2 MIN (oil level)

1 green LED for "Power" indication1 red LED for "ERROR" switching contact2 yellow LEDs for status indications RxD and TxD (communication)

InputsPower supply 80...265 VAC, 40 Hz...400 Hz

80...353 VDC

Optional: 20 - 72 VDC

Power consumption: Max. of 10 VA or W

Temperature sensor Pt100 signal as per IEC 751 in 2 or 3-conductor technique or4...20 mA signal (active or passive), standard measuring range: -20° C...+140° C (others on request)Measuring converters can be provided for other input signals such as, for example, 0...1 mA or 0...10 V.Optional: The 4-20 mA input can be used to record the ambient temperature (active or passive signal), standard measuring range: -40° C...+120° C.

Current transformer input 0.5...5 A CT nominal currentOptional: Model with clamp-on current transformer for cable diameters up to max. of Ø10 mm

Inputs of OL/CT module 2 x 0.5...5 A CT nominal current (current transformer input)(additional) 4...20 mA signal (active or passive), measuring range: 0...100% for oil level

Inputs of the IM module 2 analog inputs4 floating inputs for loaded switching elements with 80-250 VAC/DC, optional for 20-40 VAC/DC

OutputsAnalog outputs 1 oil temperature (Oil Temp.), temperature range: -20° C...+140° C

1 winding temperature (Winding), temperature range: 0° C...+160° C

Outputs of OL/CT module 2 winding temperature (WT2 and WT3), temperature range: 0° C...160° C(additional) 2 oil level (OL1 and OL2), output range: 0...100%

Interfaces Basic module 1 USB, socket, type B (Service Interface)1 RS485 on terminals1 USB, socket, type B (Service Interface)1 RS232, D-Sub socket1 RS485 on terminals1 RJ45, socket (LAN, modem, thermet)1 fiber-optic conductor connection, FH-ST plug connector for transmitter and receiver (850 mm)

Relays Basic module 6 change-over contacts for fan control or messages1 change-over contact for device self-monitoring

OL/CT module 6 change-over contacts for messages

Status LEDs: For basic module

For OL/CT module

For IM module

IM-module


Messko

www.messko.com©Messko GmbH 2009

Gewerbegebiet An den Drei Hasen,Messko-Platz 161440 Oberursel, Germany

Telephone +49 (0)61 71 63 98-0 Fax +49 (0)61 71 63 [email protected]

Please note: Details of the information in all our publications may differfrom the actually delivered device. We reserve the right to make alterations without notice.

Subject to change without prior noticeIN 2075/02/01 • 01/09/1500 • Art. no. 990911 • Printed in Germany


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Monitor Tra Messko MTeC_EPT202_en[1]