Datasheet

ManualsBrandsWelwyn ManualsPassive ComponentsWirewound Resistor 2W, 100Ohm, 5%

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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.

02.12

Construction

A high purity ceramic rod is assembled with interference ﬁt end caps to which are welded the terminations. The surge withstanding resistive element

is wound on the rod and welded to the caps. Flameproof fusible cement coating is applied prior to marking with indelible ink. The components are

then leadformed if required and packed.

Marking

ULW2 & ULW3 resistors are marked with ﬁve colour bands. The ﬁrst four indicate value and tolerance in conformance with IEC62. The ﬁfth yellow

band denotes deﬁned fusibility. ULW4 and ULW5 resistors are legend marked with type, value and tolerance.

ULW2 ULW3 ULW4 ULW5

Power rating at 25°C watts 2 3 4 5

5 second overload rating at 25ºC watts 10 15 20 25

Inrush / surge performance See Pulse Performance graphs

Resistance range ohms 4R7 to 100 4R7 to 100 10 4R7-100

TCR ppm/°C ±200

Isolation voltage volts 250 350 500

Resistance tolerance % 5

UL recognised standard values ohms 4R7, 10, 22, 33,

47, 68, 100

4R7, 10, 22, 27,

33, 39, 47, 68, 100

4R7, 10, 22, 27,

33, 47, 68, 100

Thermal impedance °C/watt 110 82 62 54

Ambient temperature range °C -55 to +155

UL Recognised

Wirewound Resistors

ULW Series

Physical Data

· UL1412 recognised fusible resistor *

· Failsafe mains fusing at 120 / 240Vrms

· Inrush and surge withstanding

· UL94-V0 ﬂameproof coating

· SMD leadform option available

· RoHS compliant

* UL ﬁle number E234469.

Electrical Data

Dimensions (mm) and weight (g)

Type L Max D Max f min d nom

PCB

mount

centres

Min

bend

radius

Wt.

Nom

ULW2

9.0 3.8 19.8

0.8

12.7

1.2

0.5

ULW3

14.5 5.8 24.6 20.3 1.1

ULW4

13 5.6 22.8 18.9 1.0

ULW5

16.5 7.2 23.6 22.9 1.8

Note - no limiting element voltage applies; maximum continuous voltage is √(P.R)

Summary of content (5 pages)

PAGE 1
UL Recognised Wirewound Resistors ULW Series · · · · · · UL1412 recognised fusible resistor * Failsafe mains fusing at 120 / 240Vrms Inrush and surge withstanding UL94-V0 flameproof coating SMD leadform option available RoHS compliant * UL file number E234469.
PAGE 2
UL Recognised Wirewound Resistors ULW Series Terminations Material: Strength: Solderability: Hot tin dipped copper wire The terminations meet the requirements of IEC 68.2.21 The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 Solvent Resistance The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits.
PAGE 3
UL Recognised Wirewound Resistors ULW Series Pulse E (J) ULW3 Pulse ULW2 E (J) ULW5 ULW3 Value ohms 10 4.7 5.3ohms 4.3 Value 1.7 3.6 10 4.7 10.42 9.73 4.3 5.3 1.7 3.6 10.42 9.73 Pulse Performance ULW2 ULW5 22 3.2 1 22 11.35 3.2 27 3.9 1.3 27 9.51 3.9 1 11.35 1.3 9.51 33 5.3 1.7 33 8.89 5.3 39 2.8 1.75 39 10.3 2.8 1.7 8.89 47 4.9 1.8 47 12.66 4.9 1.75 10.3 1.8 12.66 1.2/50μs Peak Voltage Limit (10 pulses at 10s intervals, ΔR<5%) Note the voltage shown is the nett voltage across the resistor.
PAGE 4
UL Recognised Wirewound Resistors ULW Series Fusing Performance Maximum Fusing Time (s) ULW3 & ULW4 Fusing Characteristic 60 50 40 30 20 10 0 50 60 70 80 90 100 110 120 Initial Power (W) Maximum Fusing Time (s) ULW5 Fusing Characteristic 60 50 40 30 20 10 0 80 100 120 140 160 180 200 Initial Power (W) Notes: 1. Typical fusing times are around 1/3 of the maximum figures. 2. After fusing the resistance value is >100 times the initial nominal value. 3.
PAGE 5
UL Recognised Wirewound Resistors ULW Series Packaging The standard packaging for ULW is taped. The critical dimensions are shown in Figure 1. The component wires will not protrude beyond the outside edge of the tapes. Taped product is then packed into ammo boxes for ULW2, 3 and 4 or onto reels for ULW5. Alternative packaging is available by request. Pre-formed resistors are supplied loose packed in plastic bags or boxes. For SMD leadformed option, see the Z-form datasheet.