270 Series
Vitreous Enamel Power
F ꢀ at u ꢁ ꢀ S
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.
•ꢀTerminalsꢀsuitableꢀforꢀsolderingꢀ
or bolt connection
•ꢀHighꢀwattageꢀapplications
•ꢀRuggedꢀleadꢀfreeꢀvitreousꢀenamelꢀcoating
•ꢀFlameꢀresistantꢀcoating
•ꢀAll-weldedꢀconstruction
•ꢀRoHSꢀcompliantꢀavailableꢀ
Suitable for rugged applications, the 270 Type
resistors feature all-welded construction and durable
lead free vitreous enamel coating. Mounting brackets •ꢀ“Fastꢀon”ꢀoptionꢀ–ꢀseeꢀterminalꢀ538,ꢀ
not included with resistors.
https://www.ohmite.com/assets/docs/terminals.pdf
SꢀꢁIꢀS SPꢀCIFICatIONS
Non-Inductive versions available;
Other sizes available; Also available in
low cost Centohm or Silicone coating;
Consult Ohmite.
Series
L12
L25
Wattage
12
Ohms
0.1-51K
Core Code
Max. Voltage*
565
Std. Terminal
D
K
K
M
P
P
S
S
57
40
40
40
46
46
45
45
25
50
0.15-100K
0.38-260K
0.23-101K
0.13-101K
0.16-129K
0.38-218K
0.69-392K
625
1625
2845
3595
4595
4970
8900
* Maximum Voltage is based on
Ohm’s Law [V=√P*R] as limited by the
resistance value of specified product
or the voltage limit stated, whichever
is lower.
L50
L100
L175
L225
L500
L1000
100
175
225
500
1000
ChaꢁaCtꢀꢁIStICS
Lead free vitreous enamel. Large models (500 watts and up) are supplied in Silicone Ceramic.
Also available in low-cost Centohm coating; Consult factory.
Coating
Tubular ceramic.
Core
Terminals
Derating
Solder coated radial lug. RoHS solder composition is 96% Sn, 3.5% Ag, 0.5% Cu
Linearly from 100% @ +25°C to 0% @ +350°C.
±5% 1Ω and over (J); ±10% under 1Ω (K)
Based on 25°C free air rating.
Tolerance
Power rating
Overload
10 times rated wattage for 5 seconds.
1 to 20Ω: ±400 ppm/°C; Above 20Ω: ±260 ppm/°C
Temperature coefficient
1000 VAC: 12 to 100 watt rating. 3000 VAC: 175 to 225 watt rating (Measured from terminal to
Dielectric withstanding voltage
mounting bracket)
use the formula √P/R
Max. amps
When resistance exceeds the resistance values listed, derate the Power Rating by 25% to
improve reliability. No power derating necessary for ratings higher than 100W.
Power limitations for
high resistance values
Power
rating
Resistance
value
12W
25W
50W
100W
3,900Ω
12,000Ω
35,000Ω
75,000Ω
see https://www.ohmite.com/assets/docs/hardware_resistor.pdf
Mounting Hardware
(continued)
1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com
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