Flame Retardant
Thermocoat
Tin Plated Copper Clad
Steel-Copper Weld®
Fully Welded
Construction
Alloy Resistance Wire Wound
To Specific Parameters On
High Thermal Conductivity
Ceramic Core
WIRE WOUND RESISTORS
SILICONE COATED TYPE
VHIA
SERIES
HIGH SURFACE TEMPERATURE
Power Silicone “Thermo Coat”
Wire Wound Resistors
Industrial / Professional Applications
• Small Size : Power Ratio.
• 0.5W to 20 Watts (at 40°C)
• Tolerances as close as 1%.
• R01 to 120K.
• TCR as low as +20ppm/°C available
depending on application and
resistance value.
• Pulse applications as per
IEC 61000-4-5.
VHIA
WIRE WOUND RESISTORS SILICONE COATED TYPE
PHYSICAL CONFIGURATION
TYPE
POWER
RATING
at 40°C
(Ambient)
0.5W
1W
1W
2.5W
2.5W
3W
3W
4W
4W
4W
4W
5W
5W
5W
7W
7W
10W
10W
10W
15W
15W
20W
20W
DIMENSIONS (mm)
L
(max)
7.0
10.9
11
13.0
13.0
12.5
15.2
16.2
16.5
13.2
23.0
17.5
23.5
23.5
25.5
32.5
44.0
44.0
44.0
50.0
50.0
67.0
67.0
D
(max)
2.7
3.2
4.3
5.5
5.5
5.1
6.0
6.9
5.5
5.5
7.2
7.5
8.5
8.5
7.5
9.5
8.5
9.8
9.8
10.0
10.0
10.0
10.0
◊
0.5 MC
1 MC
1 AC
2.5 C
2.5 C1
3 MC
3 C
4 C
4 AC
4 MC
4 CL
5 AC
5 C1
5 C
7 AC
7 C1
10 AC
10 C1
10 C
15AC
15AC1
20AC
20AC1
l
±1.5
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
38
d
±0.05
0.5
0.5
0.8
0.8
1.0
0.8
0.8
1.0
0.8
0.8
0.8
0.8
1.0
0.8
0.8
1.0
0.8
1.0
0.8
0.8
1.0
0.8
1.0
LM
±1
30
30
35
35
35
35
40
40
40
35
45
40
45
45
45
55
65
65
65
70
70
90
90
⊕
RESISTANCE RANGE TYPICAL
WT.
PER PC
min
max
(gms)
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
R01
1K6
4K0
6K2
10K
10K
7K6
14K
15K
11K
10K
47K
29K
47K
47K
39K
68K
88K
100K
100K
100K
100K
120K
120K
0.21
0.36
0.75
1.2
1.8
0.8
1.2
2.0
1.25
1.0
2.9
1.8
3.6
3.1
3.6
5.3
6.9
8.3
7.3
8.2
8.6
11.5
12.0
◊
For non-inductive types and for resistance values < 1R0
+
0.8mm allowed
⊕
For resistance values less than R10 & tolerance less than ±2% please measure resistance over centered length LM.
Note :
1. The standard terminals in this series is tinned Copper Weld®.
2. For Pulse capability please refer to Electrical data / characteristics section.
Low inductance Aryton - Perry winding type resistors are available in this series. For non-inductive types reduce
maximum resistance values shown to 50% and the continuous working voltage to 70%.
NON-INDUCTIVE RESISTOR
VHIA
WIRE WOUND RESISTORS SILICONE COATED TYPE
PRE-FORMED LEADS
The resistors terminations can be bent and cut as per requirements for quick PCB mounting.
Please send detailed drawings of the type of performing required.
PHYSICAL CONFIGURATION
100%
DERATING CURVE
Rated Dissipation [%]
83.5%
50%
0
ELECTRICAL DATA / CHARACTERISTICS
PARAMETER/PERFORMANCE TEST & TEST METHOD
Rated Ambient Temperature
Voltage Rating / Limiting Voltage /
Max Working Voltage
Dielectric Withstanding Voltage / Voltage Proof
[Test method no. 301 of MIL 202F] -
Based on limiting voltage x 2 or 500V whichever
is applicable.
Insulation Resistance
[Test method no. 302 of MIL 202F]
Short Time Overload
[Test Method - 5 secs at 5 times rated power for
3 watts and smaller; 5 secs at 10 times rated power
for 4 watts and larger]
Resistance Tolerances Available
40
100
200
0
300
350
Ambient Temperature [ C]
PERFORMANCE REQUIREMENTS
Full Power dissipation at 40°C and linearly derated
down to zero at 350°C - [Refer Derating curve above].
V = PxR
Max. ∆R ± (1% + R05). No flashover, mechanical
damage, arcing or insulation breakdown.
> 1000M (dry) > 100M (wet)
Max. ∆R ± (2% + R05)
±10%[K]; ±5% [J]; ±3%[H]; ±2%[G]; ±1%[F]
Resistor Temperature rise as a function of applied
power
[See graph displayed ]
The graph provided is general in nature and reflects
temperature rise of a few selected types for the general
guidance of the design engineer. Exact reading for any
particular HTR type and specific resistance value can be
obtained from factory on request.
VHIA
WIRE WOUND RESISTORS SILICONE COATED TYPE
Pulse Capability :
For the design engineer HTR has selected a few types and provided below, vital data in the form of charts / graphs
which illustrate two important characteristics of the pulse version of these HTR types.
Pulse On Regular Basis -
The maximum allowable peak pulse power (W) as a function of pulse duration (T) in
seconds. (Repetetive Pulse) - tp repetition time of the pulses / ti - impulse time-duration of pulse.
10000
tp/ti=1000
Peak Pulse Power (W)
1000
tp/ti=200
100
1 AC
tp/ti=50
10
tp/ti=10
tp/ti=2
1
1R5
Time (Seconds)
10000
t
p
/t
i
=1000
1000
Peak Pulse Power (W)
t
p
/t
i
=200
t
p
/t
i
=50
100
t
p
/t
i
=10
3 MC
10
t
p
/t
i
=2
1
Time (Seconds)
10000
t
p
/t
i
=1000
t
p
/t
i
=200
Peak Pulse Power (W)
1000
t
p
/t
i
=50
100
t
p
/t
i
=10
4 AC
10
t
p
/t
i
=2
1
Time (Seconds)
WIRE WOUND RESISTORS SILICONE COATED TYPE
VHIA
10000
t
p
/t
i
=1000
Peak Pulse Power (W)
1000
t
p
/t
i
=200
t
p
/t
i
=50
5 AC
100
t
p
/t
i
=10
10
t
p
/t
i
=2
R15
8K2
100R
15R 1R5
1
Time (Seconds)
10000
t
p
/t
i
=1000
t
p
/t
i
=200
Peak Pulse Power (W)
1000
t
p
/t
i
=50
100
t
p
/t
i
=10
7 AC
10
t
p
/t
i
=2
R10
16K
100R 15R 1R5
1
Time (Seconds)
10000
t
p
/t
i
=1000
t
p
/t
i
=200
1000
Peak Pulse Power (W)
t
p
/t
i
=50
10 AC
t
p
/t
i
=10
100
10
t
p
/t
i
=2
2R2
15K 240R 33R R68
1
Time (Seconds)