Select 270 Type fixed resistors
for applications requiring watt-
age ratings from 12 to 1000
watts.
The 270 Type resistors are
equipped with lug terminals
suitable for soldering or sturdy
bolt connection. When secure
mounting is required, the hol-
low core of these resistors
permit fastening with spring-
type brackets, thru bolts or
thru bolts with slotted-steel
brackets.
Suitable for rugged applica-
tions, the 270 Type resistors
feature all-welded construction
and durable lead free vitreous
enamel coating.
Mounting brackets not
included with resistors.
F E A T U R E S
• Terminals suitable for soldering
or bolt connection.
270 Series
Power Resistors
• High wattage applications.
• Rugged lead free vitreous enam-
el coating.
• Flame resistant coating.
• All-welded construction.
• RoHS compliant product avail-
able Jan. 2006 Add “E” suffix to
part number to specify.
Vitreous Enamel
C
D
L
Dimensions (in. / mm)
L
D
C
Series Wattage Ohms
Length
Diam.
I. D. Core Voltage
L12
12
0.1-51K 1.75 / 44.4 0.313 / 7.94 0.188 / 4.76 565
S P E C I F I C A T I O N S
Material
Coating: Lead free vitreous
enamel.
Core: Tubular ceramic.
Terminals: Solder coated radial
lug.
Derating: Linearly from 100% @
+25°C to 0% @ +350°C.
Electrical
L25
25 0.15-100K 2.0 / 50.8 0.562 / 14.3 0.313 / 7.94 625
L50
50 0.38-260K
100 0.23-101K
175 0.13-101K
4.0 / 101.6 0.562 / 14.3 0.313 / 7.94 1625
6.5 / 165.1 0.750 / 19.1 0.50 / 12.7 2845
8.5 / 215.9 1.125 / 28.6 0.75 / 19.1 3595
L100
L175
L225
L500
225 0.16-129K 10.5 / 266.7 1.125 / 28.6 0.75 / 19.1 4595
500 0.38-218K 12.0 / 304.8 2.50 / 63.5 1.75 / 44.5 4970
L1000 1000 0.69-392K 20.0 / 508.0 2.50 / 63.5 1.75 / 44.5 8900
Non-Inductive versions available; Other sizes available; Also available in low
cost Centohm coating; Consult Factory.
Tolerance:
±5% 1Ω and over (J)
±10% under 1Ω (K)
Power rating: Based on 25°C free
air rating.
Overload: 10 times rated wattage
for 5 seconds.
Temperature coefficient:
1 to 20Ω: ±400 ppm/°C.
Above 20Ω: ±260 ppm/°C
Dielectric withstanding voltage:
1000 VAC: 12 to 100 watt rating.
3000 VAC: 175 to 225 watt rat-
ing (Measured from terminal to
mounting bracket)
O R D E R I N G I N F O
M A D E - T O - O R D E R OPRADRETRSI N G I N F O
RoHS Compliant
Core Diameter Terminal Type
See “Core and See “Resistor Terminals
Terminal Selection” for Tubular Cores”
See page
40 for
RoHS Compliant
� ꢀ ꢁ ꢂ ꢃ ꢄ ꢄ ꢅ
Series Wattage Tolerance Ohms
custom
core and
terminal
info
� ꢀ ꢁ ꢂ ꢁ ꢃ ꢄ ꢁ ꢂ ꢅ ꢁ ꢁ ꢆ ꢇ
F = 1%
H = 3%
1R0 = 1 Ω
Tolerance
F = 1%
H = 3%
250 = 250 Ω
1K0 = 1,000 Ω
Coating
Wattage
Ohms
J
= 5%
270 = Vitreous
R500 = 0.500 Ω
K = 10% 25K = 25,000 Ω
470 = Silicone Ceramic
1R00 = 1 Ω
25K5 = 25,500 Ω
J
=
5%
250R = 250 Ω
1K00 = 1,000 Ω
25K0 = 25,000 Ω
25K5 = 25,500 Ω
K = 10%
Power limitations for high
resistance values: When
resistance exceeds the resis-
tance values listed at right,
derate the Power Rating by
25% to improve reliability:
Power Resistance
No power
derating
rating
12W
25W
50W
100W
value
3,900Ω
12,000Ω
35,000Ω
75,000Ω
necessary
for ratings
higher than
100W.
See page 34
for mounting hardware
To calculate max. amps: use the
formula √P/R
S TA N D A R D P A R T N U M B E R S F O R S TA N D A R D R E S I S TA N C E V A L U E S
Wattage
Wattage
Ohmic
value
0.51
1
1.5
2.2
3.3
4.7
6.8
10
12
15
18
22
27
33
39
47
56
68
82
Ohmic
value
470
560
680
12 Watt
12 Watt
Part No.
Prefix
Suffix
Part No.
Prefix
Suffix
L12JKR51
L12J1R0
L12J1R5
L12J2R2
L12J3R3
L12J4R7
L12J6R8
L12J10R
L12J12R
L12J15R
L12J18R
L12J22R
L12J27R
L12J33R
L12J39R
L12J47R
L12J56R
L12J68R
L12J82R
L12J100
L12J120
L12J150
L12J180
L12J220
L12J270
L12J330
L12J390
L12J470
L12J560
L12J680
L12J820
L12J1K0
L12J1K2
L12J1K5
L12J1K8
L12J2K2
L12J2K7
L12J3K3
L12J3K9
L12J4K7
L12J5K6
L12J6K8
L12J8K2
L12J10K
L12J12K
L12J15K
L12J18K
L12J22K
L12J27K
L12J33K
L12J39K
L12J47K
L12J51K
820
1
2
3
4
5
–––1R0
–––2R0
–––3R0
–––4R0
–––5R0
4,000 –––4K0
5,000 –––5K0
6,000 –––6K0
7,500 –––7K5
8,000 –––8K0
10,000 –––10K
12,000 –––12K
15,000 –––15K
20,000 –––20K
25,000 –––25K
30,000 –––30K
35,000 –––35K
40,000 –––40K
50,000 –––50K
60,000 –––60K
70,000 –––70K
75,000 –––75K
80,000 –––80K
1000
1200
1500
1800
2200
2700
3300
3900
4700
5600
6800
8200
10000
12000
15000
18000
22000
27000
33000
39000
47000
51000
10 –––10R
15 –––15R
25 –––25R
50 –––50R
75 –––75R
100 –––100
125 –––125
150 –––150
200 –––200
250 –––250
500 –––500
750 –––750
800 –––800
1,000 –––1K0
1,500 –––1K5
2,000 –––2K0
2,500 –––2K5
3,000 –––3K0
3,500 –––3K5
100
120
150
180
220
270
330
390
100,000 –––100K
125,000 –––125K
150,000 –––150K
175,000 –––175K
200,000 –––200K
250,000 –––250K
= Most popular Standard values
= Standard values
= Non-Standard values subject to minimum handling charge per item
Shaded values involve very fine resistance wire and should not be used in critical
applications without burn-in and/or thermal cycling.
Red outlined values supplied in Silicone-Ceramic coatings instead of vitreous enamel.
Ohmite Mfg. Co. 1600 Golf Rd., Suite 850, Rolling Meadows, IL 60008 • Tel. 1-866-9-OHMITE • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com