LOCO AND COACH WIRING CABLES FOR RAILWAYS

These are normally elastomeric cables & are custom built to suit invidual application in contrast with other conventional cables, design of which is more or less standardised. The most noteworthy factor for developing elastomeric cables is in its application, where in continous vibration (as loco & coach speed on rails) are of prime importance. Cable however are simple in construction but they call for utmost care in raw material selection, process control & quality awareness.
The following factor are considered when designing these cables :

1. High degree of quality & reliability during the entire span of operation.
2. Very careful selection of material due to the mechanical & environmental abuse that those cables are exposed to both during installation & in operation.
3. Utmost care in production to control & maintain within limits the dimensions of these cables.
4. Stringent quality control to ensure reliability of the product.

The prime requirement for insulation & sheath used for loco & coach wiring are as following :

INSULATION :

1. High temperature with standability
2. Good volume resistivity
3. Flexibility
4. Good mechanical strength
5. Fuel/oil resistance
6. Low water absorption
7. Low weight
8. Good electrical characteristics
9. Retention of properties at low temperature

SHEATH :

1. High mechanical strength
2. Good weather resistance
3. Good tracking resistance
4. Flexibility
5. Good oil/fuel resistance
6. High temperature with standability
7. Rentention of properties in low temperature
8. Good flame resistance

The railways have therefore opted EPR for insulation & CSP for outer sheath.

S.NO	TYPE	IDENTIFICATION	VOLTAGE GRADE	APPLICATION
1.	Flexible trailing cables	FT	1.1 kv Portable m/c	coal cutters & similiar
2.	Flexible trailing cables	FTD	1.1 Kv	Hand held m/c like drill etc.
3.	Pliable armoured Flexible Cable	P3	1.1 Kv	Conveyers,Loaders & similiar transportable m/c
4.	Pliable armoured Flexible Cable	PC	1.1 Kv	Remote control circuit
5.	Pliable armoured Flexible Cable	PL	1.1 Kv	For coal face light

1.	FT
a.	FT3 - 5 Core	5 Core around a cradile separator
b.	FT4 - 5 Core	3 Power cores with protective screen one unscreened plot clad around bare central conductor.
c.	F 16 - 5 Core	Power core with protective screen with plot lad around an elastomeric centre. Cross section range : 16 to 95 sq mm.
2.	FTD
a.	FT3 - 5 Core	3 Power core + pilot + each core all 6 sq mm. laid around cradle separator.
3.	P
a.	P3 - 5 Core	3 Power core + pilot + each core around cradle separator cross section 6 to 35 sq.mm
4.	PC
a.	PC1 -2 Core section 2.5 sqmm - 4sqmm
b.	PC2 - 5 Core section 2.5 sqmm - 4sqmm
5.	PL
a.	PL1 - 4 Core section 4 sq mm
b.	PL2 - 5 Core section 4 sq mm