background image

5

Instructional Leaflet 

IL70C1037H05

Effective October 2009

Digitrip models 520, 520i; and 520M, 520Mi,

520MC, 520MCi trip units for use only in

Magnum and Magnum DS circuit breakers

eaton corporation

 www.eaton.com

Section 1: General description of Digitrip 

trip units

Digitrip

E

 trip units are breaker subsystems that provide the 

protective functions of a circuit breaker. The trip units are in 

removable housings, installed in the breaker, and can be replaced 

or upgraded in the field by the customer. This instructional leaflet 

specifically covers the application of Digitrip trip units (see 

Tablt 1

installed in Magnum

E

 and Magnum DS breakers. Throughout this 

instructional leaflet, the use of the term “Magnum breakers” refers 

to both the Magnum and Magnum DS low voltage, AC power  

circuit breakers.
The Magnum Digitrip line of trip units consists of the 520, 520M, 

and 520MC for UL

T

 standards and models 520

i

, 520M

i

, and 520MC

i

 

for IEC standards. (See 

Tablt 1

 for available protection types.) Only 

models 520MC and 520MC

i

 provide communications. (See 

Tablt 2

 

for data that will be communicated.)
The Digitrip 520, 520M, and 520MC trip units may be applied on 

both 50 and 60 Hz systems.

Figurt 1. Digiorip 520MC Trip Unio wioh Raoing Plug

Auxiliary 

Power 

Module 

Input

Rating 

Plug

Protection 

Settings

Cause of Trip LED

INCOM 

Transmit 

LED

Test Port 

(covered)

Four- 

Character 

LCD

All trip unit models are microprocessor-based AC protection devices 

that provide true rms current sensing for the proper coordination 

with the thermal characteristics of conductors and equipment. The 

primary function of the Digitrip trip unit is circuit protection. The 

Digitrip analyzes the secondary current signals from the circuit 

breaker current sensors and, when preset current levels and time 

delay settings are exceeded, will send an initiating trip signal to the 

trip actuator of the circuit breaker. In addition to the basic protection 

function, the Digitrip 520 family of trip units provides mode of trip 

information such as:

• 

Long time trip (overload)

• 

Short time trip

• 

Instantaneous trip

• 

Ground (earth) fault trip (if supplied)

The current sensors provide operating power to the trip unit. As 

current begins to flow through the breaker, the sensors generate a 

secondary current that powers the trip unit.
The Digitrip 520 family of trip units provides five phase and two 

ground (time-current) curve shaping adjustments. To satisfy the 

protection needs of any specific installation, the exact selection of 

the available protection function adjustments is optional. The short 

delay and ground fault pickup adjustments can be set for either 

FLAT or I

2

t response. A pictorial representation of the applicable 

time-current curves for the selected protection functions is provided, 

for user reference, on the face of the trip unit as shown in 

Figurt 1

.

PrNotcoiNn

Each trip unit is completely self-contained and requires no external 

control power to operate its protection systems. It operates from 

current signal levels derived through current sensors mounted in the 

circuit breaker. The types of protection available for each model are 

shown in 

Tablt 1

 and 

Figurt 16

 through 

Figurt 27

.

Note:

N

The Digitrip 220+ (LI model—

Figurt 16

), 520 (LSI model—

Figurt 

17

), 520M (MLSI model—

Figurt 20

) and 520MC (CLSI model—

Figurt 24

can be used on three-pole or four-pole circuit breakers for the protection of 

the neutral circuit. Only these four models can provide neutral protection, 

although models MLSIA, MLSIG, MWLSIG, CLSIA, CLSIG, and CWLSIG can 

provide neutral metering. Refer to the National Electrical Code

T

 (NEC

T

) for 

the appropriate application for four-pole breakers.

MNdt Nf orip and soaous infNrmaoiNn

On all models, a green light emitting diode (LED), labeled Status, 

blinks approximately once each second to indicate that the trip unit 

is operating normally. This Status LED will also blink at a faster rate 

if the Digitrip is in a pickup, or overload, mode.
Red LEDs on the face of the trip units (for long delay, short delay, 

and instantaneous) flash to indicate the cause, or trip mode, for 

an automatic trip operation (for example, ground fault, overload, 

or short circuit trip). A battery in the Digitrip unit maintains the trip 

indication until the Reset/Battery Test button is pushed. The battery 

is satisfactory if its LED lights green when the Battery Check button 

is pushed (see Section 6).

Note:

N

The Digitrip unit provides all protection functions regardless of the 

status of the battery. The battery is only needed to maintain the automatic 

trip indication.

Summary of Contents for 520

Page 1: ...URES EATON IS NOT LIABLE FOR THE MISAPPLICATION OR MISINSTALLATION OF ITS PRODUCTS m WARNING OBSERVE ALL RECOMMENDATIONS NOTES CAUTIONS AND WARNINGS RELATING TO THE SAFETY OF PERSONNEL AND EQUIPMENT O...

Page 2: ...g 17 Section 4 Protection settings 22 General 22 Long delay current setting 22 Long delay time setting 23 Short delay current setting 23 Short delay time setting 23 Instantaneous current setting 24 Gr...

Page 3: ...LSIG 19 Figure 20 Digitrip 520M MLSI 20 Figure 21 Digitrip 520M MLSIA 20 Figure 22 Digitrip 520M MLSIG 20 Figure 23 Digitrip 520Mi MWLSIG 20 Figure 24 Digitrip 520MC CLSI 21 List of figures Descriptio...

Page 4: ...r use only in Magnum and Magnum DS circuit breakers eaton corporation www eaton com List of tables Description Page Table 1 Protection Types Available for Digitrip Trip Units 6 Table 2 Communication F...

Page 5: ...unit As current begins to flow through the breaker the sensors generate a secondary current that powers the trip unit The Digitrip 520 family of trip units provides five phase and two ground time curr...

Page 6: ...s Yes Yes Ground earth fault protection Ground fault option Yes Yes Yes Ground fault alarm No Yes d Yes d Ground fault pickup 25 100 x In c 25 100 x In c 25 100 x In c Ground fault delay I2 t at 0 625...

Page 7: ...messages alarm Overload long pickup X X X X High load alarm X N A N A N A Ground alarm N A X b X X b Remote messages trip Long delay trip X X X X Short delay trip X X X X Instantaneous trip X X X X G...

Page 8: ...OM ITS CONNECTOR DAMAGE TO INTERNAL CURRENT TRANSFORMERS MAY OCCUR DUE TO AN OPEN CIRCUIT CONDITION m CAUTION IF A RATING PLUG IS NOT INSTALLED IN THE TRIP UNIT THE UNIT WILL INITIATE A TRIP WHEN IT I...

Page 9: ...irements The cover is held in place by two cover screws Security is ensured by the insertion of a standard meter seal through the holes in both of the cover retention screws The plexiglass cover has a...

Page 10: ...etting for a time in excess of a 0 1 second delay The alarm relay will reset automatically if the ground current is less than the ground fault pickup see Figure 5 Note 4 High load alarm 520M 520MC mod...

Page 11: ...the force of the compressed spring by the permanent magnet When a tripping action is initiated the low energy trip actuator coil receives a tripping pulse from the Digitrip unit This pulse overcomes...

Page 12: ...ultiple ground scheme is shown in Figure 14 In this figure a ground fault is shown that has two possible return paths via the neutral back to its source The three neutral sensors are interconnected to...

Page 13: ...summed together at the PC board donut transformer to sense ground fault via element R5 b No jumper on secondary contacts B 6 B 7 c Neutral input if four wire is via contacts B 4 B 5 Neutral current in...

Page 14: ...3000 1 H13 3200 1 H14 630 1 H15 1250 1 H16 3150 1 H17 4000 1 H18 100 1 All secondary currents to be 1 00A nominal at full scale Insulation level 0 6 kV BIL 10 kV full wave Continuous thermal current r...

Page 15: ...ground sensing c This scheme is not applicable to four pole breakers No secondary contacts B 4 and B 5 are available on four pole breakers Do not jumper B 6 B 7 in four pole applications Ground Retur...

Page 16: ...B 7 to program the Digitrip to use element R4 c This scheme is not applicable to four pole breakers R5 R5 R5 T M2 M1 B5 B4 I 2 G I 2 G I 2 G I 2 G IG IG ig ig i 2 g i 2 G i 2 g i 2 g i 2 g N in B5 B5...

Page 17: ...s are digitized by the CHip chip The microcomputer continually digitizes these signals This data is used to calculate true rms current values which are then continually compared with the protection fu...

Page 18: ...e affected parts of the system When zone interlocking is employed a fault within the zone of protection of the breaker will cause the Digitrip 520 family of units to Trip the affected breaker immediat...

Page 19: ...models 520 520i and 520M 520Mi 520MC 520MCi trip units for use only in Magnum and Magnum DS circuit breakers eaton corporation www eaton com Figure 16 Digitrip 520 LI Figure 17 Digitrip 520 LSI Digit...

Page 20: ...rip models 520 520i and 520M 520Mi 520MC 520MCi trip units for use only in Magnum and Magnum DS circuit breakers eaton corporation www eaton com Figure 20 Digitrip 520M MLSI Figure 21 Digitrip 520M ML...

Page 21: ...7 8 9 95 1 0 t Response I2 Dependent on In In Max Amp Rating Current Sensor Rating Battery Check Reset Battery Test Step Unit Status Catalog 2 4 7 10 12 15 20 24 Short Delay Setting Short Delay Time...

Page 22: ...ound current settings are defined in multiples of In To illustrate the effect of each protection curve setting simulated time current curves are pictured on the face of the trip unit Each rotary switc...

Page 23: ...g Plug Long delay time setting There are eight available long delay time settings as illustrated in Figure 31 ranging from 2 24 seconds These settings are the total clearing times when the current val...

Page 24: ...nstantaneous Current Settings Ground fault current setting The eight ground fault current settings are labeled with values from 0 25 to 1 0 x In see Figure 36 The domestic U S models have a maximum of...

Page 25: ...ace Module BIM can be used to monitor up to 31 Digitrip 520MC trip units The acceptable addresses are 001 031 Remote master computer When desired Digitrip 520MC trip units can communicate with a BIM o...

Page 26: ...PING OPERATION WILL CAUSE DISRUPTION OF SERVICE AND POSSIBLE PERSONAL INJURY RESULTING IN THE UNNECESSARY SWITCHING OF CONNECTED EQUIPMENT m CAUTION TESTING A CIRCUIT BREAKER WHILE IT IS IN SERVICE AN...

Page 27: ...trip unit LEDs A and B function to represent sufficient battery voltage from both the single lithium cell and the six alkaline batteries respectively If either LED does not light or lights only dimly...

Page 28: ...d from the Cell A B C Suitable Conductors Low Voltage AC Current Source Primary Disconnect Stabs When Drawout Polarity and Identification A B C Suitable Conductors Low Voltage AC Current Source Primar...

Page 29: ...ip and associated Cause of Trip LEDs see Figure 15 Insulating Tab Rating Plug Door Flipped Open Use Type 1 3 N Lithium Battery Only Pull to Remove Battery Pull Out After Installation Battery installat...

Page 30: ...LE SENSOR RATING MATCHES THAT PRINTED ON THE RATING PLUG DOOR INSTALLING A RATING PLUG THAT DOES NOT MATCH THE SENSOR RATING CAN PRODUCE SERIOUS MISCOORDINATION AND OR FAILURE OF THE PROTECTION SYSTEM...

Page 31: ...gitrip 220P or 520 LI L curve 70C1296 Digitrip 220P or 520 LI I curve 70C1006 Digitrip 520 LS curve 70C1007 Digitrip 520 I curve 70C1008 Digitrip 520 G curve 70C1446 Digitrip 520MC Maintenance Mode tr...

Page 32: ...d A blue LED confirms that the function is on For the other two methods of arming the Maintenance Mode function this switch must be in the position labeled 0 1 With this setting a remote switch wired...

Page 33: ...A blue LED on the Digitrip verifies that Maintenance Mode is armed b The recommended selector switch for this low voltage application is Eaton part number 10250T1333 2E which includes a contact block...

Page 34: ...e fault and will send an interlocking signal to the main trip unit The main trip unit will begin to time out and in the event that the feeder breaker Z2 does not clear the fault the main breaker will...

Page 35: ...in Magnum and Magnum DS circuit breakers eaton corporation www eaton com Figure 49 Typical Zone Interlocking Connections with Two Main Breakers M1 M2 and a Tie Breaker T F23 C ZO ZI F22 C ZO ZI T C Z...

Page 36: ...er See Section 2 Notes Trip unit is malfunctioning Replace trip unit High inrush phase currents may cause fictitious ground pickup momentarily Connect Zout to Zin jumper to provide some time delay see...

Page 37: ...INPUT 520M ONLY Z_COM BRKCLSD K2 8 K2 9 K2 7 K2 6 K2 5 K2 4 K2 3 K2 2 K2 1 A 30 A 29 A 27 A 28 B 19 B 18 OPTIONAL AUX SWITCH 52b 52a B 17 B 16 A 22 A 21 A 19 A 20 A 26 A 25 OPTIONAL AUX SWITCH 52b 52...

Page 38: ...COM network uses a 3 pin The RS 485 Modbus uses a 4 pin connector that consists of signals A B COMmon and SHielD Three baud rates of 1200 9600 or 19200 are selectable via programming switch for the Mo...

Page 39: ...structional Leaflet IL70C1037H05 Effective October 2009 Digitrip models 520 520i and 520M 520Mi 520MC 520MCi trip units for use only in Magnum and Magnum DS circuit breakers eaton corporation www eato...

Page 40: ...and conditions outlined in appropriate Eaton selling policies or other contractual agreement between Eaton and the purchaser THERE ARE NO UNDERSTANDINGS AGREEMENTS WARRANTIES EXPRESSED OR IMPLIED INC...

Reviews: