Red Spot Fuse Holders FAQ

Details: Categorie: Eaton Bussmann BS88 Fusegear

Red Spot Colour

The standard finish is Black, but fuse holders in White, Grey or Green colours can be supplied as follows:

White: RS20H, RS20P, RS20F, RS32H. RS32P, RS63H, RS63P, RS100H, RS100P, RS200H, RS200P.

Grey: RS20H, RS20P.

Green: RS20H, RS2OP, RS2OF, RS32H, RS32P.

Black fuse holders are for fuse links.

White fuse holders are for copper links.

Grey and Green fuse holders are for special purpose.

Red Spot Fuse Link Selection

Fuse Link selection

Select a rating of fuse link which is at least equal to the normal full load current of the circuit, including any allowances needed for harmonic currents, as in the case p.f. correction circuits.
Ensure that the fuse link rating can withstand any over currents which may apply to the circuit, such as transformer in-rush currents, motor starting surges and repetitive cycle loads.
When full cable protection is required, ensure that the fuse link rating is compatible with the selected cable, i.e. less than or equal to cable rating.

Fuseholder rating	'RED SPOT' HRF fuse link to BS88:Part 2: 1988 660 Volt a.c.	Extended Range of 'RED SPOT' HRC fuse links to BS 88: Part 2: 1988 for motor circuit protection
Amp	TYPE:	TYPE:	Current rating Amp	Rating for motor starting Amp
20	NIT2-20A	NIT20M251 NIT20M321	20 20	25 32

32	TIA2-32A	TIA32M35 TIA32M40 TIA32M50 TIA32M63	32 32 32 32	35 40 50 63

63	TIA2-32A TIS35-63A	TIS63M80 TIS63M100	63 63	80 100

100	TIA2-32A TIS35-63A TCP63-100A	TCP100M125 TCP100M160 TCP100M200	100 100 100	125 160 200

200	TBC2-3A TC80 & 100A TF125-200A	TF200M250 TF200M315	200 200	250 315

400	TKM250 & 350A TM355 & 400A	TM400M450	400	450

Recommended minimum torque values

Rating	Fuse Link fixing screw		Cable terminal screw		Back connected stud

	Size	Torque	Size	Torque	Size	Torque

RS20	4BA (Ø35mm)	1,2Nm	1/4” BSF grub screw	2,0Nm	M6	3,0Nm
	Pan head	(11 lb.in)	(Slotted)	(18 lb.in)		(27 lb.in)

RS32	2BA (Ø45mm)	2,0Nm	1/4” BSF grub screw	2,0Nm	M6	3,0Nm
	Pan head	(18 lb.in)	(Slotted)	(18 lb.in)		(27 lb.in)

RS63	2BA (Ø45mm)	2,0Nm	3/8” BSF grub screw	3,5Nm	M8	6,0Nm
	Pan head	(18 lb.in)	(Slotted)	(31 lb.in)		(53 lb.in)

RS100	M6	2,5Nm	1/2” BSF grub screw	4,0Nm	M10	10,0Nm
	Pan head	(22 lb.in)	(Slotted)	(35 lb.in)		(89 lb.in)

RS200	M6	2,5Nm	5/8” BSF hex head	25,0Nm	M12	14,0Nm
	Pan head	(22 lb.in)	(18mm A/F)	(18,5 lb.ft)		(10 lb.ft)

RS400	M8	6,0Nm	5/8” BSF hex head	25,0Nm	M16	25,0Nm
	Hex head	(53 lb.in)	(18mm A/F)	(18,5 lb.ft)		(18,5 lb.ft)

Note:	Conversion from Nm to lb.in.	1Nm = 8,85075 lb.in.

Red Spot Fuseholder Installation

Method of cabling

Front connected fuse holders

Remove Red nylon insulating shroud to release cable sleeve.
Remove cable sleeve.
Fit cable sleeve over cable.
Fit conductor into fuse base terminal and tighten cable clamping screw to secure.
Replace Red nylon shroud taking care it holds the cable sleeve in position by locating the shroud in the groove provided by the sleeves.

Cable selection and termination

Ensure cable sizes are correctly chosen in line with the IEE Wiring Regulations (BS 7671), making due allowance for:

i. Grouping of cables (correction factor Cg).
ii. Ambient temperature / internal enclosure temperature (correction factor Ca).

Ensure that maximum cable core temperature is restricted to 70°C or less.
Ensure adequate cable length is provided for interconnections between fuse holders or other components. This will prevent possible heat input to the fuse holder which could result in overheating.
If using multi-stranded cables / Tri-rated cables the bared strands should be crimped in thin wall copper ferrules in order to consolidate the strands. The following points should be taken into account:

i. The inside diameter of the ferrules should match that of bared cable ends.
ii. The ferrule lengths should be the same length as the cable entry tunnel in the fuse base terminals.
iii. The termination screw should compress the wall of the ferrules, providing further consolidation of the cable strands within the ferrule.

When used in banks, ensure that the diversity factors recommended in BS5486 Part 11, Factory Built Assemblies, are applied. If the number of fuse holders banked together exceeds 12 a 0.6 diversity factor may be used.
For applications when there is insufficient or no diversity applied, adequate compensation should be made by a combination of some, or all, of the following:

i. Utilise higher standard current rated fuse links, or motor rated fuse links.
ii. Increase the cable size.
iii. Ensure that fuse holders in the bank are separated by at least 5mm.
iv. Ensure that there is adequate spacing between fuse banks if they are stacked vertically. Typically, depending on rating, this would be 30-50mm.
v. Incorporate natural or forced ventilation.

These measures should ensure that the heat is adequately exported
from the fuses.

Sharp bends in cables, especially near termination points, should be avoided in order to prevent damage to cable cores or insulation and to ensure that no mechanical strain, is put on the contact block in the fuse
base.
The minimum torque values detailed in the attached table should be applied to cable terminal and fuse link fixing screws.

Important note:
These products should be installed, commissioned and maintained by, or under the supervision of, a competent person, in accordance with current Electricity at Work Regulations, IEE Regulations for the Electrical Equipment of buildings, Statutory requirements and any other specific instructions issued by GE Power Controls Ltd. These notes assume throughout that the product is isolated from the supply during installation or maintenance. It is essential that this is done before commencement of any work. Any covers, or other safety measures which are removed during installation or maintenance must be replaced on completion.

Red Spot Maintenance

Guidelines

To ensure satisfactory operation of these fuse holders throughout their service life, it is recommended that the following procedure be carried out at regular intervals (at least once a year) as part of a planned maintenance schedule. Where the environment or service duty is severe there may be a need for inspection at shorter intervals.

Procedure

Isolate the supply.
Withdraw the fuse carriers and inspect fuse tags and carrier contacts for any signs of damage.
Check all cable terminal screws and fuse link fixing screws to ensure that the correct torque has been applied.
Wipe clean and remove any oxidation from the carrier contacts.
Apply a small amount of a proprietary electrical contact lubricating grease after ensuring that all contact areas are clean.
Re-fit the fuse carriers and re-connect the supply.

Important Note

The use to which these products are put and their service environment are outside our control. Therefore, particular care should be taken to follow these guidelines during installation or maintenance. No responsibility can be accepted by GE Power Controls Ltd if these guidelines are not followed.

Source: GE Red Spot Catalogue