WHS-UL Series

Wirewound High Surge

UL Recognised Fusible Resistors

Packaging

The standard packaging for axial WHS-UL is taped. The critical dimensions are shown below. The component wires will not protrude

beyond the outside edge of the tapes. Taped product is then packed into boxes or onto reels. See Ordering Procedure for quantities.

Dimensions (mm)

a

b

c

WHS2UL

6

52

5

WHS3UL

6

67

10

WHS5UL

6

63

10

Wirewound High Surge

UL Recognised Fusible Resistors

WHS-UL Series

General Note

TT Electronics reserves the right to make changes in product specification without notice or liability.

All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.

www.ttelectronics.com/resistors

BI Technologies IRC Welwyn

Dimensions (mm)

a

b

c

WHS2UL

6

52

5

WHS3UL

6

67

10

WHS5UL

6

63

10

Application Notes

1. If the resistors are to dissipate full rated power, it is recommended that the terminations should not be soldered

closer than 4mm from the body.

2. Due to operating temperature limits imposed by some PCB materials, derating may be necessary. The surface

temperature rise at the centre of the body is shown under Thermal Performance.

3. For the purposes of UL approval, the following points should be observed:

3.1 To protect against fire under all conditions of overload, a positive clearance of at least 13mm should

be provided between the resistor body and any combustible materials.

3.2 A positive clearance of 13mm should be provided between the resistor body or terminations and

uninsulated parts of opposite polarity or uninsulated dead metal parts.

3.3 Limited Short Circuit testing should be performed in the complete appliance.

Leadforming Options

1. WHS-UL resistors can be supplied with goalpost or lancet pre-formed leads. Hairpin form is also available on

WHS2UL and WHS3UL only. For dimensions and ordering details see:

https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Resistors/ApplicationNotes/TN008-resistors-Leadform-Capability.pdf.

2. WHS-UL resistors are also available in an SMD format with ZI formed leads, packed in blister tape. For dimensions

and ordering details see: https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Resistors/Datasheets/ZI-form.pdf

3. A radial taped version is also available for WHS3UL only as shown below.

Radial Taped Dimensions (mm)

Dimension

Notation WHS3ULR

Component body length

L

14.5 max

Component body diameter

D

5.8 max

Application Notes

Leadforming Options

1. If the resistors are to dissipate full rated power, it is recommended that the terminations should not be soldered closer

than 4mm from the body.

2. Due to operating temperature limits imposed by some PCB materials, derating may be necessary. The surface

temperature rise at the centre of the body is shown under Thermal Performance.

3. For the purposes of UL approval, the following points should be observed:

3.1

To protect against fire under all conditions of overload, a positive clearance of at least 13mm should be

provided between the resistor body and any combustible materials.

3.2

A positive clearance of 13mm should be provided between the resistor body or terminations and

uninsulated parts of opposite polarity or uninsulated dead metal parts.

3.3

Limited Short Circuit testing should be performed in the complete appliance.

1. WHS-UL resistors can be supplied with goalpost or lancet pre-formed leads. Hairpin form is also available on WHS2UL

and WHS3UL only. For dimensions and ordering details see:

https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Application-Note/TN008-Resistors-Leadform-Capability.pdf

2. WHS-UL resistors are also available in an SMD format with ZI formed leads, packed in blister tape. For dimensions and

ordering details see: https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Resistors/Datasheets/ZI-form.pdf

Wirewound High Surge

UL Recognised Fusible Resistors

WHS-UL Series

General Note

TT Electronics reserves the right to make changes in product specification without notice or liability.

All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.

www.ttelectronics.com/resistors

BI Technologies IRC Welwyn

Dimensions (mm)

a

b

c

WHS2UL

6

52

5

WHS3UL

6

67

10

WHS5UL

6

63

10

Application Notes

1. If the resistors are to dissipate full rated power, it is recommended that the terminations should not be soldered

closer than 4mm from the body.

2. Due to operating temperature limits imposed by some PCB materials, derating may be necessary. The surface

temperature rise at the centre of the body is shown under Thermal Performance.

3. For the purposes of UL approval, the following points should be observed:

3.1 To protect against fire under all conditions of overload, a positive clearance of at least 13mm should

be provided between the resistor body and any combustible materials.

3.2 A positive clearance of 13mm should be provided between the resistor body or terminations and

uninsulated parts of opposite polarity or uninsulated dead metal parts.

3.3 Limited Short Circuit testing should be performed in the complete appliance.

Leadforming Options

1. WHS-UL resistors can be supplied with goalpost or lancet pre-formed leads. Hairpin form is also available on

WHS2UL and WHS3UL only. For dimensions and ordering details see:

https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Resistors/ApplicationNotes/TN008-resistors-Leadform-Capability.pdf.

2. WHS-UL resistors are also available in an SMD format with ZI formed leads, packed in blister tape. For dimensions

and ordering details see: https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Resistors/Datasheets/ZI-form.pdf

3. A radial taped version is also available for WHS3UL only as shown below.

Radial Taped Dimensions (mm)

Dimension

Notation WHS3ULR

Component body length

L

14.5 max

Component body diameter

D

5.8 max

10.24

General Note

TT Electronics reserves the right to make changes in product specification without notice or liability.

All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.

© TT Electronics plc

www.ttelectronics.com/resistors

BI Technologies IRC Welwyn