Answer / karthik

MC61 relay is an IDMT Over current+Earth fault relay.It is a
product of L&T company.
there are many models in them namely,
1)MC61C
2)MC61A
etc

Answer / praveen

3 Phase O/C + E/F + Highset
0C 0
50/51 RYBN
Numerical Relay
Lowset O/C -Is
Highset O/C -Ihs
Lowset E/F -Os
Highset E/F -Ohs
O/C Is = 20-200% Step 5%
E/F Os = 5-80% Step 5%
HS O/C = (0.2 to 40) x In step of -
0.2 In or disable
HS E/F = (0.1 to 20) x On step of -
0.1 On or disable
Time Characteristics available -
NI, VI, EI, or Definite Time
TMS : 0.1 - 1.6 Step 0.05
Site selectable Trip time Char.
Highset can be disabled
Display of Currents, Trip count
Self supervision feature
£ 0.25 VA on CT/Phase
Not applicable
0 to 60 C
< 2kg £ 10 VA
1 N/O Contact for self suprvn
Draw out
121 x 158 x 224
113 x 142
20-110V AC / DC or
88-264V AC / DC
1 AMP or 5 AMP
(site selectable)
4NO or 2NO + 2NC

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