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T O S H I B A

6 .  

6.1 Current setting

(1) When detected current is in a range of 0.5   

After confirming that the current value under 

 load

condition is in a range of 0.5   

 set the current

adjusting knob to the desired detecting value.

 When detected current is above 

Using an external CT (current transformer), 

 suited

for the detected Current value, connect the secondary side of

the CT to the 

 

  o f   t h e   r e l a y .   C a l c u l a t e   t h e

secondary current 

 to the detected current

value, based on the CT ratio.

Then set the current adjusting

Knob to this calculated value.

6.2 Setting the detection delay 

Setting time varies depending 

 each individual 

Adjust the detection delay 

 according to the following:

 

  l o a d

TO avoid detection during start-up, set the delay tire to

 120% of starting 

(2) 

 load

If the inrush current (inrush time varies 

 

  i s   l a r g e ,   s e t   t h e   d e l a y  

 to 

1 2 0 %   o f   t h i s   i n r u s h  

 

   the 

  i s

 inrush 

 is short and therefore, even when the

adjusting knob is set at the 

 position. there should

not be any nuisance tripping.

 

Summary of Contents for Current Relay RC803A-HP1

Page 1: ...TOSHIBA I NSTRUCTI O N M A N U A L C U R R E N T R E L A Y RC803A HP1 TOSHIEA C O R P O R A T I O N ...

Page 2: ... n o n M o t o r s 0 b 3 L i m i t i n g S t a r t i n g C u r r e n t o f R o t o r s 9 4 4 Transformers __ __ __ ___ ___ 10 4 5 H e a t e r s Laape a n d O t h e r C i r c u i t s 10 5 Mounting ____ ___ _ _ _____________________ 10 6 A d j u s t a e n t s __ _ ______ ___________________ 1 2 6 1 Current Setting ____ _ _____ ______________________ 1 2 6 2 S e t t i n g t h e D e t e c t i o n D e ...

Page 3: ...xcessive current such as inrush current lay exceed rated current flow in motor or transforaer circuits this current relay has an adjustable delay circuit to prevent it fro operating during start up Further this current relay is fail safe The relay ooerates at the saae tile control Dower is applied and the relay is de energized when the inout signal exceeds the Dreset level or control Dower is remo...

Page 4: ... range Detection delay tile adjustable range Operating volt SPECIFICATIDHS 5A continuous 0 5 5A For current above this range use a CT current transforrer and connect the relay to its secondary side low voltage circuit below AC 6OOV 3 To detect current in high voltage circuits use a CT and connect the relay to its secondary side Overcurrent Undercurrent 0 1 3s 0 1 30s a5 132VAC 170 250VAC 50 6Diiz ...

Page 5: ...t30Y Between terminals and ground 2DOOVAC f o r 1 in Between terminals and ground 1 X 40 s a t 45OOV s t a n d a r d w a v e f o r m B e t w e e n t e r m i n a l s a n d g r o u n d 1DOH Ohm o r more w h e n m e a s u r e d w i t h a SDOVDC a e g g e r A m p l i t u d e 2 5 20Hz 26 156 4 0 t i m e s o f m a x c o n t i n u o u s c u r r e n t SAI f o r 1 s e c agglied t w i c e i n a c c o r d a ...

Page 6: ... current exceeds the detection circuit operating level the detection delay timer is actuated If over current is continuously detected for more then the detection delay time set value the overcurrent response delay timer is actuated Then if overcurrent is detected when the resDonse delay timer has elapsed the overcurrent relay is actuated If current drops below the undercurrent detection set ValUe ...

Page 7: ... Undercurrent detect img FiD 1 Characteristics 1 APDl ication 4 1 Overcurrent Detection on Hotors An aDDlication example Is shown in Fig 2 In this clrcult an excessive load is detected by detecting the overcurrent of a motor and the lain circuit is ooend to Protect 6 ...

Page 8: ... high voltage circuit use an external CT and connect the secondary side of CT to the relay as shown in the following figure AC3 Phase Power SuDDly Ll Y 23 1 I A I I1 I Current relay Note T h e RCB03 s OUtDUt contacts are shown with Dower source aDDl ied TiD 2 ADDlication ExaaDle using An External CT ...

Page 9: ...ection delay timer has elapsed the relay is actuated when the set tiue of the response delay tiler is over 4 2 Undercurrent Detection on Hotors To utilize the undercurrent detection function the relay is used in a notor circuit with a fixed load to detect livht or no load conditions For examDIe in the case of a DUUD UOtOr this relay is used to detect undercurrent when the VOlUue Of water SUDDlied ...

Page 10: ... current of Rotors Many eotors of uediua and large capacity use a aethod to start by limiting starting current 8y detectino the lain circuit current this relay can automatically advance the starting resistance on the secondary side of the motor in this case the knob of the detection delay timar and that of the resoonse delay timer should be kept at the minimum settings 9 ...

Page 11: ...current condition is detected by the relay For exaeDle this relay can be used to detect the disconnection of heater circuits on constant temperature ovens or heatar circuits for insulators on transmission and distribution facilities In extremely cold regions 5 Hount ing See Fig 4 for uounting dieensions Be careful not to use this relay in the following conditions 1 Locations in aebient teeperature...

Page 12: ...TOSHISA 6F9E0090 50 3 7 Hole 7z Hountino holes Fig 4 Dimensions B 3 t ll ...

Page 13: ...to the detected current value based on the CT ratio Then set the current adjusting Knob to this calculated value 6 2 Setting the detection delay tiae Setting time varies depending upon each individual aDDlication Adjust the detection delay tile according to the following 1 Hotor load TO avoid detection during start up set the delay tire to aDDroxisately 120 of starting tile 2 Transformer load If t...

Page 14: ...y not need any delay tile It is aainly used to prevent nuisance trioging ride through by ignoring aoeentary load gliches 7 Ooerational l e s t 1 Check both the control and detection circuits to confirm there is no eis wiring 2 Check if the current dedtction tiae delay and resgonse tiae delay settings are correct 3 If the wiring ard settings are correct energize the control circuit and check if it ...

Page 15: ... is aDDlied turn the rain circuit switch ON and Derforg the following checks a In the case of a motor load If the set start up tiae delay is too short the relay say be actuated In such a case reset the detection delay tiae adjusting knob accordingly After the start up tiae delay has exDired apply current above the set detection value to confirm that the relay functions after the resoonse delay til...

Page 16: ...urrent State is detected and the relay drops out Refer to Fig 5 Caution If input signal to this current relay is zero When StoDDed it is not possible to judge if it is undercurrent or in a disconnected state In this case it is recommended to have a circuit connecting a normally oDen auxiliary con tact of the Dain circuit switch in series with the alara or IauD circuit this will Drevent the relay f...

Page 17: ... by gradually reducing the setting of the current adjusting knob If the relay still does not ooerate it is defective In this case please contact the dealer froa which you purchased the relay or Toshiba Power Source Detected current Overcurrent detect ion Undercurrant I T3 detect ion I Tl Detection delay tire T2 Overcurrent detecting resgonse delay tiler T3 Undercurrent detecting resgonse delay tla...

Page 18: ...ver must be raaoved Reaove the cover by amlYing a force in the direction of the arrow as shown below To replace the cover place the projection of the cover in the slip out oreventive hole and then insert the bosses of the cover into the 2 holes at the uooer left and right Cover Ak i z 17 ...

Page 19: ... T O S H I B A C O R P O R A T I O N ...

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