Omega MSH Specification

Strip Heaters

Mica Insulated Strip Heaters

MSH Series

*

Typical Applications

l Food Warming Equipment
l Packaging Equipment
l Blow Molding Equipment
l Testing Equipment
l Vulcanizing Presses
l Vending Machines
l Hot Plates
l Ovens
l Molds
l Kettles
l Incubators

An economical, practical and reliable heat source
capable of providing uniform heat transfer to flat surfaces.

Mica insulated strip heaters are used in hundreds
of industrial and commercial heating applications.

Specially treated rust­resistant steel sheath
casing provides the best
combination of physical
strength, high emissivity and
good thermal conductivity
for sheath temperatures
up to 480°C (900°F). For
corrosive atmospheres and/
or sheath temperatures up
to 650°C (1200°F), stainless
steel sheath is available.

* Mica Strip heaters are UL recognized and CSA certified in many design variations. Omega’s UL file number is E65652 and CSA file number is 043099.
If you require UL, CSA, or other NRTL agency approvals, please specify when ordering.

For maximum connecting
surface, the specially
designed stainless steel
screw terminals are securely
fastened to a connecting
jumper, assuring positive
contact with the windings,
providing maximum
current carrying capacity.
For other terminal or lead
arrangements, see pages
3 and 4.

Specially selected mica
grade and thickness is used
to insulate the windings,
providing excellent thermal
conductivity and dielectric
strength.

A specific nickel-chrome
resistance ribbon wire size
is properly engineered
to achieve the best
combination of wire gauge
and spacing between
turns, thereby providing
the lowest winding
temperature possible.
The ribbon wire is wound
on a specially selected Mica
Strip, providing even heat
distribution for maximum
heater life.

To order, call 1-800-826-6342 or shop online at omega.com

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Specifications and Tolerances

Strip Heaters

If tighter tolerances are required consult OMEGA. A heater’s
physical size combined with electrical ratings will determine
the actual minimums and maximums.

Performance Ratings

Maximum Sheath Temperature:

Rust Resistant Steel: 480°C (900°F)
Stainless Steel: 650°C (1200°F)

Nominal Watt Density: 5 to 45 Watt/in2 (0.8 to 7.0 Watt/cm2)

Maximum Watt Density: Depends on operating

temperature and heater size; 38 Watt/in2 (5.9 Watt/cm2)
Maximum when UL and CSA approval is required

Electrical Specifications

Maximum Voltage: 480V

Maximum Amperage:

Lead Wire Termination: 10 A
Screw Terminations: 8-32UNF—20 A; 10-32UNF—25 A

Resistance Tolerance: 10%, −5%

Wattage Tolerance: 5%, −10%

Formula for Calculating Watt Density

Watt Density =

* Cold area consists of holes or cutouts.

(Heater Width - 3⁄8) × (Heater Length - Cold Area*)

Heater Wattage

Material Specifications and Physical Sizes

Standard Sheath Material: Rust resistant steel
Optional: Stainless steel or aluminum

Nominal Thickness: 4.76 mm (3⁄16")

Minimum Width: 15.88 mm (5⁄8"), may vary depending

on termination

Width Tolerance: ± 0.79 mm (1⁄32")

Maximum Length: 1829 mm (72")

Length Tolerance: Up to 610 mm (24") ± 1.59 mm (1⁄16")

Over 610 mm (24") ± 3.18 mm (1⁄8")

Screw Terminals:

25.4 mm (1") Wide Strips: 8-32 threads
Over 25.4 mm (1") Wide Strips: 10-32 threads

Minimum Termination Distance from Edge of Heater

No Mounting Tabs With Mounting Tabs

Installation Instructions

1. Mica insulated strip heaters are available with mounting
slots at each end for surface mounting applications or
without mounting slots for insertion into milled slots.

2. For surface mounting installations, mica strip heaters must
be clamped securely along their entire length to a smooth
metal surface by using metal clamps 76 to 127 mm
(3 to 5") apart.

3. Holes along the body of the strip heater for mounting
purposes are not recommended and should only be used
when there is no other means of clamping the strip heater
down. These holes take up valuable winding space,
increasing watt density, resulting in poor heater life.

4. When supported by mounting slots, the terminal end
should be secured firmly. Opposite end should be slightly
loosened to allow for linear expansion.

5. The surface being heated must be clean and smooth
for efficient heat transfer. Small air gaps caused by
imperfections can cause hot spots, resulting in heater
failure.

6. Contaminants such as oil, plastics, and dirt should not
be allowed to collect on heaters, as they will find their
way into the heater windings, eventually carbonizing and
causing electrical shorts.

2

To order, call 1-800-826-6342 or shop online at omega.com

SM

Strip Heaters

Screw Terminal Terminations

Type T1

Screw terminals at opposite ends.
Minimum width required is 22 mm (

Note: Typical Termination locations
shown (pages 3 and 4). Specify
terminal locations when ordering.

Type B

Low-profile 10-32 button
terminals with binding head
screws. Same location and
minimum width requirements
as types T1, T2 and T3. 6-32
threads available.

Type B1 Terminals at opposite

ends (see T1)

Type B2 Terminals same end

(see T2)

Type B3 Terminals same end (shown)

Height

7

⁄8").

Type T2

Screw terminals tandem at one end.
Minimum width required is 22 mm (

Post Terminals
(center to center)
8-32: A=3⁄4"
10-32: A=7⁄8"

Terminal Protection

Type C

Terminal box has one
13 mm (1⁄2") trade size
knockout [actual diameter
22 mm (7⁄8")] for ease of wiring.
It provides excellent protection
against exposed terminals. Boxes
can be prewired with armor cable
or wire braid.

Type CA Box only

A

Button Terminals
(center to center)
6-32: A= 11⁄8"
10-32: A= 7⁄8"

Type CB Box with galvanized cable

Type CC Box with stainless steel cable

Type CD Box with wire braid

7

⁄8").

A

Type T3

Screw terminals parallel at one end.
Minimum width required is 51 mm (2").

Post Terminals
(center to center)
8-32: A=3⁄4"
10-32: A=7⁄8"

Height

A

Type P1

High-Temperature quick-disconnect plug. Available on
22 mm (7⁄8") widths (depending on termination configuration)
and wider with cup and plug assembly or just cup. Type
P1Q shown with 90° plug and galvanized armor cable. Other
options available. Consult OMEGA.

Igloo™

Igloo ceramic terminal
covers consist of two
ceramic parts. With a
tight-fitting cap and a solid
base, an Igloo cover will fully
insulate any standard 8-32
or 10-32 terminal lug used for
electrical wiring hookup. Igloo
covers can be assembled onto
any standard mica strips with 10-32
screw terminals. Igloo covers are
available in 3 different styles: single
port, double port in-line and double
port 90°. For specific model numbers
visit omega.com. Heater with double port
in-line Igloo cover shown here.

To order, call 1-800-826-6342 or shop online at omega.com

SM

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Strip Heaters

Lead Wire Terminations

Type W1

Wire braid leads offer sharp bending not
possible with armor cable. 254 mm (10")
of wire braid over 305 mm (12") leads
is standard. If longer braid or leads are
required, specify. Minimum width
required is 22 mm (

Type L1

Flexible lead wire exiting from the
top through a brass eyelet. 254 mm
(10") long leads standard; if longer leads
are required, specify. Minimum width
required is 22 mm (7⁄8").

7

⁄8").

Type W2

Flexible stainless steel braided lead
wires exiting at same end. 254 mm (10")
stainless steel braid over 305 mm (12")
leads is standard. If longer braid or leads
are required, specify. Minimum width
required is 29 mm (1

Type L2

Flexible lead wire exiting same end.
254 mm (10") long leads standard;
if longer leads are required, specify.
Minimum width required is 29 mm (11⁄8").

1

⁄8").

Type W3

Flexible stainless steel braided lead wires
exiting at opposite ends. 254 mm (10")
stainless steel braid over 305 mm (12")
leads is standard. If longer braid or leads
are required, specify. Minimum width
required is 19 mm (3⁄4").

Type L3

Flexible lead wire exiting at opposite
ends. 254 mm (10") long leads standard;
if longer leads are required, specify.
Minimum width required is 19 mm (3⁄4").

Abrasion Resistant Terminations

Type R1

Armor cable provides far superior protection
to lead wires where abrasion is a constant
problem. Available with 2- or 3-prong plugs.
254 mm (10") of armor cable over 305 mm (12")
leads is standard. If longer cable, leads or plugs
are required, specify. Minimum width required is
25 mm (1").

Type R1A Galvanized cable, crimped

Type R1B Stainless Steel cable, crimped

Type R1C Galvanized cable, tack welded

Type R1D Stainless Steel cable, tack welded

Type R1E Galvanized cable, full silver brazing

Type R1F Stainless Steel, full silver brazing

4

To order, call 1-800-826-6342 or shop online at omega.com

Type R2

Right-angle
armor cable can
be positioned in
any direction.
254 mm (10") of
armor cable over
305 mm (12") leads is
standard. If longer leads
are required, specify.
Minimum width required is
32 mm (11⁄4").

Type R2A Galvanized

cable, crimped

Type R2B Stainless steel cable,

crimped

Type R2C Plain leads, no cable

SM

Strip Heaters

Additional Mica Strip Heater Optional Features

Disc Heater

When ordering disc heaters, specify
outside diameter, electrical ratings,
and termination type. If mounting
holes are required, specify location
and hole size.

Ring Heaters

When ordering ring heaters, specify inside and outside diameters, electrical ratings,
and termination type. If mounting holes are required, specify location and hole size.

Custom Engineered/Manufactured

Irregular Shape

Mica strip heaters can be made into any practical
shape and electrical rating. We welcome your inquires.

Non-Metal Sheath Custom Mica Heaters

Open Element

This economical heater design without the metal case
is commonly used in laminating machines. The heater
assembly can be suspended or sandwiched between
non-metallic machine parts, eliminating the need for
additional and expensive metal cases.

Sinuated (Serpentine)
Element Design

Sinuated (serpentine)
wound coil design
is used for low
temperature and
low watt density
applications
within the
3 to 10 A
range.

Distributed Wattage

A mica strip heater can be designed with varying heat profile
along the length for uneven heat distribution.

Strip Heaters shown on this page are a small

representation of the many Custom Engineered and

Manufactured designs Omega has produced.

If you have a special application and need free

technical assistance, consult our team of professionals

Irregular Shape

Non-metal sheath strip heaters can be made into any
practical shape and electrical rating. We welcome
your inquires.

with your requirements. We welcome your inquiries.

To order, call 1-800-826-6342 or shop online at omega.com

SM

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Strip Heaters

Sizes and Ratings

Model numbers shown are for heaters without mounting slots. Termination Types L1 and L2 have 254 mm (10") leads.
R1 and R2 have 254 mm (10") galvanized armor cable over 305 mm (12") leads. W1 and W2 have 254 mm (10") stainless steel
braid over 305 mm (12") leads.

To Order Visit omega.com/msh for Pricing and Details

Model No. Width Length

MSH00001

—
—
—

—
MSH00007
MSH00008

—

—
MSH00011
MSH00013

—

—
MSH00016

—

—

MSH00019
MSH00020

—

—

MSH00023

—

—

—

—
MSH00028

—
MSH00030
MSH00031
MSH00032
MSH00033

—

—

—

—

—

—

—

—

—

—

—
MSH00045
MSH00047

MSH00048

—
MSH00050
MSH00051

MSH00002
MSH00003
MSH00004
MSH00005

MSH00006

—
—

MSH00009

MSH00010
MSH00012

—

MSH00014

MSH00015

—
MSH00017
MSH00018

—

—
MSH00021
MSH00022

—
MSH00024
MSH00025
MSH00026

MSH00027

—
MSH00029

—

—

—

—
MSH00034

MSH00035
MSH00036
MSH00037
MSH00038

MSH00039
MSH00040
MSH00041
MSH00042

MSH00043
MSH00044
MSH00046

—

—
MSH00049

—

—

25.4

25.4

31.8

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

38.1

50.8

50.8

50.8

50.8

50.8

50.8

50.8

50.8

50.8

50.8

50.8

50.8

61.9

63.5

63.5

63.5

63.5

63.5

73.0

73.0

76.2

76.2

1
11⁄2

1
11⁄2
11⁄2
11⁄2

1
11⁄2
11⁄2
11⁄2

1
11⁄2
11⁄2
11⁄2

1
11⁄2
11⁄2
11⁄2

1
11⁄2
11⁄2
11⁄2

1
11⁄2

2

21⁄2

2
21⁄2
21⁄2
21⁄2

2
27⁄8

1
1

1

⁄4

1

⁄2

1

⁄2

1

⁄2

1

⁄2

1

⁄2

1

⁄2

2
2
2
2
2
2

2
2
2
2

2
2

7

⁄16

1

⁄2

7

⁄8

3
3

152.4

571.5

1016.0

139.7

139.7

139.7

152.4

152.4

203.2

203.2

203.2

241.3

254.0

266.7

279.4

279.4

304.8

355.6

406.4

431.8

457.2

571.5

609.6

762.0

914.4

914.4

76.2

101.6

101.6

101.6

101.6

101.6

101.6

101.6

101.6

203.2

698.5

1092.2

139.7

101.6

152.4

215.9

254.0

355.6

152.4

152.4

177.8

177.8

6

221⁄2

40

1

5

51⁄2
51⁄2

6
6

8
8
8

91⁄2

10

101⁄2

11
11

12
14
16
17

18

221⁄2

24
30

36
36

3
4
4
4
4
4

4
4
4
8

271⁄2

43

51⁄2

4

6

81⁄2

10
14

6
6
7
7

Watts

100
525
750

⁄2

225

225
125
300
250

355
400
400
200

450
250
500
600

400
500
600
500

500

775
1000
1000

1000
1000

100

20
30
40
50

100

100

150

200

275

1200
1400

350

150

350

350

350

625

300

300

200

500

Watt Density

2

Watt/in

5
6
5
7

7
4
8
7

7
8
8
3

7
4
7
8

5
5
6
4

4
5
6
5

4
4
5
1
1
1
2
3

3
5
6
4

4
3
6
4

5
3
3
4

4
4
2
5

32
39
31
44

44
25
53
44

45
51
51
21

44
23
44
53

32
34
36
28

26
32
39
31

25
25
31

10
21

21
31
41
24

28
21
38
24

33
22
18
23

24
24
13
32

2

Termination120V 240V mm inch mm inch Watt/cm

L2

W1

R2

L1

L2

T2

L2

W1

L2
L2

T2

L2

L2

T2

L1

W1

L2

T2

L2
L1

L2

W1

L2
L2

L2
T2
T2

4
6
8

T2
T2
T2
T2
T3

W1
W1
W1

L1

L2
T2
T3
T1

R1
T3

L2

L2

T3
T3

L1

L1

6

To order, call 1-800-826-6342 or shop online at omega.com

SM

Strip Heaters

Model No. Width Length

Watt Density

Watts

MSH00052

—

MSH00054

—

—
—

MSH00058

—

MSH00060

—
—
—

—
—
—
—

—

MSH00069

—
—

MSH00072

—
—

MSH00075

Ordering Example: MSH00052, 76.2 mm (3") wide, 304.8 mm (12") long strip heater, 120V, 180 watts.

—

MSH00053

—

MSH00055

MSH00056
MSH00057

—

MSH00059

—
MSH00061
MSH00062
MSH00063

MSH00064
MSH00065
MSH00066
MSH00067

MSH00068

—
MSH00070
MSH00071

—
MSH00073
MSH00074

—

76.2

76.2

76.2

76.2

88.9

88.9

88.9

88.9

88.9

101.6

101.6

101.6

101.6

111.1

120.7

120.7

123.8

149.2

152.4

152.4

177.8

203.2

203.2

254.0

3
3
3
3

3
31⁄2
31⁄2
31⁄2

3

4
4
4

4
4
43⁄4
43⁄4

4
57⁄8

6

6

7

8

8

10

304.8

317.5

381.0

660.4

1

⁄2

101.6

114.3

190.5

254.0

1

⁄2

355.6

101.6

203.2

279.4

508.0

3

⁄8

179.4

139.7

285.8

7

⁄8

290.5

279.4

304.8

381.0

292.1

235.0

254.0

457.2

12

121⁄2

15
26

4

1

⁄2

4
71⁄2

10

14

4
8

11

20

71⁄16

51⁄2

111⁄4

117⁄16

11
12
15

1

11

91⁄4

10
18

180
300
500
600

100
500
500
900

450
275
425
750

1750

800
700
200

1200

425

1200

575

⁄2

625
450
450
300

1
2
2
1

2
7
4
5

2
4
3
3

4
5
6
1

4
1
3
1

1
1
1
0

2

Watt/in

6
10
14

9

11
46
25
32

11
25
17
21

25
33
36

4

26

8
19

7

9

7

7

2

2

Termination120V 240V mm inch mm inch Watt/cm

T1
T3

L1

R1

W2
W1

T3

W2

B3
R2
T3
T3

R1

W2

T2
T3

T3
R1
T3
T3

R1
T3
T3
B3

Custom Engineered/Manufactured Heaters

An electric heater can be very application specific; for sizes
and ratings not listed, Omega will design and manufacture a
mica insulated heater to meet your requirements.

Additional Mica Strip Heater Optional Features

Butt Case

Recommended for
heating applications where
strip heater will be placed in a
milled slot between two steel plates.

Four Sides Closed

Mica Strip Heaters can be
closed on all four sides to reduce
contamination from getting inside the
heater. Recommended on all strip heaters
over 64 mm (21⁄2") in width.

Please Specify the Following:

l Width l Termination Type
l Length l Lead Length
l Wattage l Cable/Braid Length
l Voltage l Optional Features

Mounting Method 1

Pressure Plate

Strip Heaters can

Built-In Pressure
Plate

be made with
built-in pressure
plate to add rigidity
and minimize warping
of the heater. Standard
plate thickness is 3 mm
(1⁄8"). Specify plate
thickness and choice
of mounting method 1
or mounting
method 2.

Mounting Method 2
Separate Pressure
Plate

Cross-Section-Formed

Strip Heaters can be formed on their cross
section for pipe heating applications. 51 mm (2")
minimum width required. Specify diameter of pipe
on which heaters are to be mounted.

To order, call 1-800-826-6342 or shop online at omega.com

SM

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