TT electronics 1601, 1905, 1600, 1602, 1906 Technical data

Tubular Vitreous Enamelled
Wirewound Resistors	Welwyn Components

1600/1900 Series

•Impervious lead free vitreous enamel coating

•Can be supplied with fixed, adjustable, tapped or low inductance winding

•Seven termination styles with choice of mounting arrangements

•Manufactured RoHS compliant Pb-free terminations*

*Check status of stock when ordering

General Information

Vitreous enamelled wirewound resistors are capable of withstanding a higher dissipation size for size, than any other protected type; this is attributable to the higher operating temperature which the wire and enamel can withstand. Vitreous enamel provides exceptionally good protection to the wire element and is essentially impervious to moisture. The resistors can safely be used in harsh environmental conditions.

The Welwyn range is based on thirteen sizes of tube, each of which has a recommended maximum dissipation which limits operating surface temperature to a maximum of 375°C.

The stability and high reliability of Welwyn tubular vitreous resistors is a direct result of the best quality materials being used in their construction.

High purity ceramic tubes have been matched with nickel

chromium resistance wires and specially formulated enamel to ensure that the resistors can withstand repeated heat cycling without damage.

Connections between the resistance element and end terminations are welded; other connections are brazed.

Mounting devices are available which permit resistors to be mounted by both ends or by one end. Single ended mounting is recommended for applications which do not subject the resistor to shock or vibration.

Ferrules and the F type mounting plug are anchored into the tubes with high temperature adhesive.

Special requirements, for types or styles not described in this brochure, will be considered for economic quantities.

Electrical Data

Power rating at 70°C	watts
Resistance range	ohms
Limiting element voltage	volts
TCR (-55 to +200°C)	ppm/°C
Resistance tolerance	%
Values
Thermal impedance	°C/watt
Operating temperature range	°C
Power rating at 70°C	watts
Resistance range	ohms
Limiting element voltage	volts
TCR (-55 to +200°C)	ppm/°C
Resistance tolerance	%
Values
Thermal impedance	°C/watt
Operating temperature range	°C-	55

Note See Figure 1 for curves of temperature rise / watts dissipation.

General Note

Welwyn Components reserves the right to make changes in product specification without notice All information is subject to Welwyn’s own data, relates to current manufacture and is considered

© Welwyn Components Limited · Bedlington, Northumberland NE22 7AA, UK

Telephone: [phone] · Facsimile: [phone] · Email: [e-mail] · Website: www.welwyn-tt.com

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Tubular Vitreous Enamelled

Wirewound Resistors

1600/1900 Series	Welwyn Components

Electrical Data (continued)

Table 1

		*Dissipation (watts) to						Resistance range (ohms)					Limiting			Low inductance
			produce operating										element			winding resistance
	hotspot temperature (°C) of:												voltage				range (ohms)
		Ambient = 20°C				Ambient			Minimum				Termination			Min. res. at
						= 70°C		resistance at						style
												Max. at							Max. at
Type												any							either
	200		300	375		375	±5%		±2%		±1%	tolerance	C		All others	±10%		±5%	tolerance
1601	5		10	14		11	1		15		25	15k	250		150	10		50	1.3k
1905	7		14.5	20		16	1		15		30	30k	-		450	10		50	3.5k
1600	7.5		15	21		16.5	1		15		30	56k	-		600	10		50	5.0k
1602	8		15.5	22		17	1		20		25	43k	500		350	10		50	4.0k
1906	9.5		19	28		22	1		20		30	50k	700		550	10		50	5.5k
1603	11		22	32		25	1		20		30	83k	850		750	10		50	7.5k
1604	15.5		31	45		35	1		20		60	100k	1300		1000	15		50	11.5k
1605	21		41	59		47	1		30		40	100k	1100		900	15		50	14k
1908	24		47	68		54	1		30		40	100k	1200		1000	10		50	16k
1607	34		66	95		76	1		30		50	100k	1300		900	15		50	22k
1606	41		80	115		91	1		30		40	160k	2100		1900	15		50	32k
1608	52		101	145		115	1		30		50	180k	2100		1800	20		50	38k
1609	74		145	208		165	1		35		50	250k	3000		2500	30		100	58k

*The stated dissipation applies to resistors mounted horizontally with unobstructed bore.

Performance Data

		Max		Typ
Load : 1000 hours at 70°C	∆R%	5.0		3.5
Shelf life : 12 months at room temperature	∆R%	1.0		0.1
Climatic	∆R%	0.5		0.35
Long term damp heat	∆R%	0.2		0.05
Bump and vibration	∆R%	0.1		0.02
Noise (in a decade of frequency)	∆R%	zero		zero
Pulse Handling Data			Available by request

© Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
Telephone: [phone] · Facsimile: [phone] · Email: [e-mail] · Website: www.welwyn-tt.com	Issue E · 10.05

122

Tubular Vitreous Enamelled

Wirewound Resistors

1600/1900 Series	Welwyn Components

Physical Data

Table 2 Dimensions in millimetres. See fig 2-8 for styles

	A	B	C	D	E	F	G	H	J	K
Type	max	max	max	nom	max	max	nom	±.25		max
1601	33.0	17.5	8.2	4.5	5.0	19.5	15	3.0	M3	59
1905	56.1	14.5	6.55	4.5	5.0	17.5	10	3.0	M3	-
1600	61.5	14.5	6.55	4.5	5.0	17.5	10	3.0	M3	-
1602	51.0	17.5	8.2	4.5	5.0	19.5	15	3.0	M3	77
1906	64.3	17.5	8.2	4.5	5.0	19.5	15	3.0	M3	90
1603	74.5	17.5	8.2	4.5	5.0	19.5	15	3.0	M3	101
1604	102	17.5	8.2	4.5	5.0	19.5	15	3.0	M3	128
1605	89.5	24.0	13.2	5.7	6.8	26.5	17	4.0	M4	122
1908	102	24.0	13.2	5.7	6.8	26.5	17	4.0	M4	134
1607	102	32.0	19.2	7.0	9.8	32.0	22	6.4	M6	134
1606	166	24.0	13.2	5.7	6.8	26.5	17	4.0	M4	198
1608	152	32.0	19.2	7.0	9.8	32.0	22	6.4	M6	184
1609	216	32.0	19.2	7.0	9.8	32.0	22	6.4	M6	248

Terminations

Styles B, 4B, AP and AW are available in all 13 tube sizes.

Styles C, CB and CP are available in sizes 1601 to 1609 inclusive, 1906 and 1908

Lugs (Figure 2): Pb free solder coated nickel iron. Denoted by prefix B to size reference, thus B1602

Pigtails (Figure 3): 14/.193 mm copper, 150 mm minimum length. Denoted by prefix AP, thus AP1602

Rigid wires (Figure 4): 1.2 mm diameter tinned copper, 32 mm minimum length.

Denoted by prefix AW, thus: AW1602

Lugs with screws, nuts and washers (Figure 5): Nickel plated brass screws and nuts. Denoted by prefix 4B, thus: 4B1602.

Ferrule, electrically isolated (Figure 6) Connection to resistor via Pb free solder coated nickle iron lugs. Denoted by prefix CB, thus: CB1602.

Ferrule, electrically live (Figure 7) Nickel plated brass. Denoted by prefix C, thus: C1602.

Ferrule, electrically isolated (Figure 8): Connection to resistor via pigtails of 14/.193 mm copper, 150mm minimum length. Denoted by prefix CP thus: CP1602

Marking The resistors are legend marked with type reference, resistance value, tolerance and manufacturing date code. Value marking conforms to IEC 62.

Solvent resistance: The vitreous coating and marking are resistant to all accepted industrial cleaning fluids.

© Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
Telephone: [phone] · Facsimile: [phone] · Email: [e-mail] · Website: www.welwyn-tt.com	Issue E · 10.05

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