L100

RES-270 OHMITE

Document overview

• PDF pages: 2

Technical content

Page 1

270 Series

Vitreous Enamel Power

Select 270 Type fixed resistors for applications

requiring wattage ratings from 12 to 1000 watts.

The 270 Type resistors are equipped with lug termi-

nals suitable for soldering or sturdy bolt connection.

When secure mounting is required, the hollow core

of these resistors permit fastening with spring-type

brackets, thru bolts or thru bolts with slotted-steel

brackets.

Suitable for rugged applications, the 270 Type

resistors feature all-welded construction and durable

lead free vitreous enamel coating. Mounting brackets

not included with resistors.

• Flame resistant coating
• All-welded construction
• RoHS compliant available
• “Fast on” option – see terminal 538,

http://www.ohmite.com/techdata/terminals.pdf

S E R I E S S P E C I F I C AT I O N S

Series

Wattage

Ohms

Core Code

Voltage

Std. Terminal

Non-Inductive versions available; Other sizes available; Also available in

L12

12 0.1-51K

D

565

57 low cost Centohm or Silicone coating; Consult Ohmite.

L25

25 0.15-100K

K

625

40 \* Maximum Voltage is based on Ohm’s Law [V=√P\*R] as limited by the

L50

50 0.38-260K

K

1625

40 resistance value of specified product

L100

100 0.23-101K

M

2845

40

L175

175 0.13-101K

P

3595

46

L225

225 0.16-129K

P

4595

46

L500

500 0.38-218K

S

4970

45

L1000

1000

0.69-392K

S

8900

45

c h a r a c t e r i s t i c s

Coating Lead free vitreous enamel. Large models (500 watts and up) are supplied in Silicone Ceramic. Also available in low-cost Centohm coating; Consult factory. Core Tubular ceramic. Terminals Solder coated radial lug. RoHS solder composition is 96% Sn, 3.5% Ag, 0.5% Cu Derating Linearly from 100% @ +25°C to 0% @ +350°C. Tolerance ±5% 1Ω and over (J); ±10% under 1Ω (K) Based on 25°C free air rating.

Power 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 rating (Measured from terminal to

mounting bracket) use the formula √P/R Max. amps Power limitations for When resistance exceeds the resistance values listed, derate the Power Rating by 25% to high resistance values improve reliability. No power derating necessary for ratings higher than 100W.

Power Resistance rating value 12W 3,900Ω 25W 12,000Ω 50W 35,000Ω 100W 75,000Ω

Mounting Hardware see http://www.ohmite.com/techdata/lug-mounting.php

(continued)

1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com

Page 2

270 Series

Vitreous Enamel Power

d i m e n s i o n s

in./mm

Series Wattage

L D C Core Code\* Std. Term.\*\*

L12 12 1.75 / 44.4 0.313 / 7.94 0.188 / 4.76

D 57

L25 25 2.0 / 50.8 0.562 / 14.3 0.313 / 7.94

K 40

L50 50 4.0 / 101.6 0.562 / 14.3 0.313 / 7.94

K 40

C L100 100 6.5 / 165.1 0.750 / 19.1 0.50 / 12.7

M 40

D

L175 175 8.5 / 215.9 1.125 / 28.6 0.75 / 19.1

P 46

L

L225 225 10.5 / 266.7 1.125 / 28.6 0.75 / 19.1

P 46

L500 500 12.0 / 304.8 2.50 / 63.5 1.75 / 44.5

S 45

L1000 1000 20.0 / 508.0 2.50 / 63.5 1.75 / 44.5

S 45

\* http://www.ohmite.com/techdata/200-210-270-custom.pdf \*\* http://www.ohmite.com/techdata/terminals.pdf

o r d e r i n g i n f o r m at i o n

Standard

Non-inductive F = Fast on Blank = Standard

RoHS N = Non-inductive Compliant (optional)

L 2 5 J 1 0 0 E

Series Wattage Tolerance Ohms J = 5% 1R0 = 1Ω

Coating

K = 10% 250 = 250Ω

Blank = Vitreous

1K0 = 1,000Ω

C = Centohm

25K = 25,000Ω

S = Silicone

25K5 = 25,500Ω

Standard part numbers for 270 series

Made-to-order

Core Diameter

Non-inductive

See “Core and

Blank = Standard

RoHS Compliant

N = Non-inductive Terminal Selection”

Wattage Ohms Tolerance

Coating

R500 = 0.500Ω J = 5%

270 = Vitreous

1R00 = 1Ω K = 10%

470 = Silicone Ceramic

Terminal Type 250R = 250Ω

See “Resistor Terminals

1K00 = 1,000Ω for Tubular Cores” 25K0 = 25,000Ω 25K5 = 25,500Ω

See website for custom core and terminal info

 = Standard values; check availability using the worldwide

inventory search at www.ohmite.com Red outlined values supplied in Silicone-Ceramic coatings instead of vitreous enamel.

150,000 –––150KE 

1,500 –––1K5E 

   200,000 –––200KE 

2,000 –––2K0E 

   

250,000 –––250KE 

1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com