- Safety precautions - Before installation, operation, maintenance, and inspection, please be sure to read this instruction manual and all other attached documents thoroughly in order to work safely with the equipment. Please ensure that you fully understand the equipment, safety information, and precautions that need to be taken before working with the equipment.
*The equipment must only be operated and handled by qualified personnel. Otherwise, there are risks of electric shock, injury, failure, malfunction, and maloperation. *Handling and maintenance of the equipment must only be carried out after gaining a thorough understanding of the instruction manual.
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MITSUBISHI ELECTRIC CORPORATION prior to such applications. If the user applies MITSUBISHI ELECTRIC CORPORATION products to such applications without any contact to our technical section, MITSUBISHI ELECTRIC CORPORATION shall not be liable for any items and not be insured, independently from mentioned in this clause.
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5. Onerous repair term after discontinuation of product (1) MITSUBISHI ELECTRIC CORPORATION shall accept onerous product repairs for 7 years after production is discontinued. (However, the product which was made over 15 years is recommended to replace.) (2) Product supply (including repair parts) is not available after production is discontinued.
However, this increase is limited only when all The numerical display turns on for 3 seconds when the of the relays are composed of New MELPRO-A series. If setting value is changed, which enables to check another series are combined, the number of connectable setting values easily.
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Max. 20 relays can be connected through V extension terminal (M-N) of the Number of relay connection relay which is directly connected to MPD-3 type ZVT. By turning the indicator select switch to "TEST" and pushing "TEST" button Test button for 2 seconds or more, output contact can be forced to operate (except for (Forced operation) the case of LOCK setting).
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Characteristics (MDG-A3V type relay + MZT type ZCT + MPD-3 type ZVT combination) Item Characteristics Ambient temperature: –20 to +60℃ (Under the state where dew condensation or freezing does not occur) Relative humidity: 30 to 80% on daily average Standard use Altitude: 2000m or lower conditions ・The state where abnormal vibration, shock, and inclination are not applied.
Variation characteristics of Input: Auxiliary power supply = AC90V~AC120V auxiliary power Criteria: Within ±10% of I and V operation values at rated voltage supply voltage Ambient temperature: -20, +60℃ Criteria: Temperature Operation values of I and V : Within ±20% of operation values at 20℃ characteristics Operating time: Within ±20% of operating time at 20℃...
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Structure Test button RUN indicated LED (Green) By turning the indicator select It shows the result of self- switch to "TEST" and pushing monitoring. It lights up in "TEST" button for 2 seconds or normal condition. more, output contact can be forced to operate (except for Numerical display LED the case of LOCK setting).
Operating Description 1. Protection function goes out. If input current is more than 1.5A, the ①The power supply can be derived from VT secondary. error message O.F. is displayed.) ②Set using condition switches according to your ③Phase measurement using condition (frequency, output contact, and The display shows the phase of zero-sequence max.
Application example a) Single circuit b) Multiple circuits (Directly supply V from MPD-3 type ZVT) MDG-A3V MDG-A3V “MZT” “MZT” ” “ ” MPD-3 “MPD-3” MDG-A3V MDG-A3V “MZT” “MZT” The number of MDG-A3V and MVG-A3V relay which can be directly connected from MPD-3 type ZVT is up to 20. However, previous models (e.g.
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Operation value settings and using condition settings 1. Operation value settings 2. Using condition settings In general, the operation value settings are set as follow, For all using condition setting switches, factory settings but these values should be set with due consideration are set to a default of OFF.
Handling precautions 1. Panel mounting ③Don't leave rotary switches with halfway (indefinite) ①Be sure to connect the "E" terminal of the relay to D- state. class grounding. ④The RUN LED lights up in the normal condition when the ②The relay of unit-drawer type (RD type) can be drawn rated auxiliary power supply is input.
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3. Operation characteristics test [MDG+ZCT+ZVT combination] ①In the field test, it is necessary to check the wiring or directionality, so the voltage is applied from the primary side (high-voltage side) of zero-sequence voltage detector. There are 2 ways to do this, either by combining the devices to form a test circuit (refer to Fig.
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Make sure that this circuit is open before test. MDG-A3V ※ AC100/110V ℓ “MZT” ℓt ※ AC100V Tripping coil DC100V Notes) ※ ※ These figures show that the V voltage is applied from the MPD-3C Phase primary side (high-voltage side) meter MPD-3W of MPD-3C capacitor simultaneously...
Terminal layout × MDG-A3V-R/RD Do not connect to the "×" terminals, or the relay may not operate properly. Fig. 2-7 Terminal layout Drawing out and housing operation of subunit (Unit-drawer type) For unit-drawer type (RD type), it is possible to draw Before the subunit is to be drawn out, ensure that the out the subunit from the case without removing external following items are checked in order not to carry out the...
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1. Procedure of drawing out Cover Drawer fixing screw ① Open the cover and remove the ② Close the cover and pull out the ③ Support the frame of subunit and drawer fixing screw. subunit with your finger hooked pull out. on the drawer handle on both sides.
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Handling of the cover 1. Opening and closing Please open the cover by placing your fingertip on the convex part in the right side of the cover as shown in Fig. 2-9. Fig. 2-9 2. How to replace the cover ・Removing the cover Open the cover, and lightly push up the upper side of the cover from the inner surface.
External dimensions and Panel cut-out φ140~φ142 2-φ7 hole Minimum pitch Fig. 2-11 MDG-A3V-R (Unit: mm) Same as the center of panel cut-out Fig. 2-12 MDG-A3V-RD (Unit: mm) Improvement on the reliability of protection function Any parts and materials applied to the protection relay have limited lifetime which will bring the degradation to the relay.
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HEAD OFFICE : 7-3 MARUNOUCHI 2-CHOME, CHIYODA-KU TOKYO, 100-8310, JAPAN First edition: Jan. 2021...