For technical questions, contact: powertron@vishaypg.com
FHR 2-3025 3818 FHR 4-3825 3825H 4618
Powertron
Document Number: 64206
Revision: 20-09-10
www.powertron.de
1
Type FHR 2-3025
FHR 2-3818
FHR 4-3825
FHR 4-3525H
FHR 4-4618
Resistance Range 0.010 to 100Ohms 0.001 to 100Ohms
Power rating
free air 70°C
for 3825H
with heatsink
3 W
40 W
3 W
5 W
50 W
Thermal Resistance Rthj-c 2.0 K/W 1.6 K/W
Tolerances
from 0R001
from 0R005
from 0R01
from 0R02
0.5% / 1% / 2% / 5%
0.25% / 0.5% / 1% / 2% / 5%
1% / 2% / 5%
0.5% / 1% / 2% / 5%
0.1% / 0.25% / 0.5% / 1% / 2% / 5%
0.1% / 0.25% / 0.5% / 1% / 2% / 5%
Stability 0.1% / 0.2% / 0.5%
(depends on stress)
Temperature Coefcient
Standard
Option 1
±15ppm/K (20 to 60°C)
R ≤ 0R2 TCR see table A next page
±15ppm/K (20 to 60°C)
±25ppm/K (20 to 60°C) for contact F
±10ppm/K (20 to 60°C)
(only contact A and K)
Max. Current 150 A / 200 A for contact F
Voltage Proof 500 VDC
Thermal EMF < 0.1µV/K
Operating Temperature Range -40 to 130°C
Resistor Material CuNiMn-Foil
Substrate anodized aluminium
Housing Epoxy
Connector Material Cu tinned
Terminals 2 4
Max. torque 1 Nm
SPECIFICATIONS
Part Number - Resistance - Contact - Tolerance
FHR 4-4618 0.050 Ohms A 1%
Ordering Information
Resistances from 0.001Ohm to 100Ohms•
Power Rating to 50Watt•
Resistance Tolerances to ±0.1%•
TCR to ±10ppm/K•
Very Low Inductance•
For technical questions, contact: powertron@vishaypg.com
FHR 2-3025 3818 FHR 4-3825 3825H 4618
Powertron
Document Number: 64206
Revision: 20-09-10
www.powertron.de
2
DR/R (ppm)
Temperature (°C)
-40
200
-20 140
120
80
6040 100
-8000
4000
2000
0
-2000
-4000
-6000
+15ppm/K
-15ppm/K
Limit 2 (3s)
Limit 1 (3s)
Nominal
DR/R
2
5
10
20
50
100
200
TCR-Shift (ppm/K)
Resistance Value (mOhm)
table A
0
20
40
60
80
100
120
25 50 85 100 115 130
Temperature of the backplate (°C)
Power ( % from
nominal power)
0.5%
0.1%
0.2%
Temperature Coefcient
SPECIFICATIONS (continued)
Dimensions
Derating
FHR 4-3825 / FHR 4-3825H Dimension mm
tol.
(±mm) inches
tol.
(±inches)
A24.00 0.2 0.94 0.008
B 38.00 0.3 1.50 0.012
C 1.40 0.4 0.06 0.016
D 4.00 0.1 0.16 0.004
E 34.00 0.3 1.34 0.012
F 17.50 0.2 0.69 0.008
G1.5x45° 0.1 0.06x45° 0.004
H 17.50 0.2 0.69 0.008
I 27.50 0.2 1.08 0.008
J (A-Contact) 1.50 0.1 0.06 0.004
J (K-Contact) 1.10 0.1 0.04 0.004
K 3.00 0.1 0.12 0.004
L 3.20 0.1 0.13 0.004
M 2.00 0.1 0.08 0.004
Nmax.5.5 0.2 max.0.22 0.008
N (Variante H) max.10.3 0.2 max.0.4 0.008
O 30.40 0.4 1.20 0.016
P 15.00 0.2 0.59 0.008
Q (A-Contact) 3.60 0.1 0.14 0.004
Q (K-Contact) 3.30 0.1 0.13 0.004
R 2.80 0.1 0.11 0.004
S (Variante H) 19.00 0.2 0.75 0.008
Power Rating Notes -
The FHR Series Resistors must be attached to a suitable heat-
sink. The maximum internal resistor temperature is 130°C.
To specify an appropriate heatsink use the following formula :
RqH = TMAX - ( P x RqR ) - TA
P
Where: RqH = Thermal Resistance of Heatsink ( K/W )
R
qR = Thermal Resistance of Resistor ( K/W )
T
MAX = Maximum Temperature of Resistor
T
A = Ambient Temperature of Heatsink ( °C )
P = Power Through Resistor ( W )
For technical questions, contact: powertron@vishaypg.com
FHR 2-3025 3818 FHR 4-3825 3825H 4618
Powertron
Document Number: 64206
Revision: 20-09-10
www.powertron.de
3
SPECIFICATIONS (continued)
Dimension mm
tol.
(±mm) inches
tol.
(±inches)
A24.00 0.2 0.94 0.008
B 38.00 0.3 1.50 0.012
C 1.50 0.2 0.06 0.008
D 4.00 0.1 0.16 0.004
E 34.00 0.3 1.34 0.012
F 17.50 0.2 0.69 0.008
G1.5x45° 0.1 0.06x45° 0.004
H 34.00 0.2 1.34 0.008
I 32.70 0.2 1.29 0.008
J 7.50 0.2 0.30 0.008
K 24.00 0.2 0.94 0.008
L 6.30 0.2 0.25 0.008
M 4.80 0.1 0.19 0.004
N 3.20 0.1 0.13 0.004
O 2.00 0.1 0.08 0.004
P 6.00 0.2 0.24 0.008
Q 15.00 0.2 0.59 0.008
R 4.10 0.7 0.16 0.028
S 3.30 0.7 0.13 0.028
Dimension mm
tol.
(±mm) inches
tol.
(±inches)
A17.00 0.1 0.67 0.004
B 46.00 0.3 1.81 0.012
C 1.40 0.4 0.06 0.016
D 8.50 0.2 0.33 0.008
E 40.00 0.3 1.57 0.012
F 34.00 0.3 1.34 0.012
G1.5x45° 0.1 0.06x45° 0.004
H 17.50 0.2 0.69 0.008
I 27.50 0.2 1.08 0.008
J (A-Contact) 1.50 0.1 0.06 0.004
J (K-Contact) 1.10 0.1 0.04 0.004
K 3.00 0.1 0.12 0.004
L 3.20 0.1 0.13 0.004
M 2.00 0.1 0.08 0.004
Nmax.5.5 0.2 max.0.22 0.008
O 23.40 0.4 0.92 0.016
P 15.00 0.2 0.59 0.008
Q (A-Contact) 3.60 0.1 0.14 0.004
Q (K-Contact) 3.30 0.1 0.13 0.004
R 2.80 0.2 0.11 0.008
FHR 4-3825F
FHR 4-4618
For technical questions, contact: powertron@vishaypg.com
FHR 2-3025 3818 FHR 4-3825 3825H 4618
Powertron
Document Number: 64206
Revision: 20-09-10
www.powertron.de
4
SPECIFICATIONS (continued)
Dimension mm
tol.
(±mm) inches
tol.
(±inches)
A24.00 0.2 0.94 0.008
B 30.00 0.2 1.18 0.008
C 1.40 0.4 0.06 0.016
D 4.00 0.1 0.16 0.004
E 27.00 0.2 1.06 0.008
F 15.00 0.2 0.59 0.008
G1.5x45° 0.1 0.06x45° 0.004
H 20.32 0.2 0.80 0.008
I (A-Contact) 1.50 0.1 0.06 0.004
I (K-Contact) 1.10 0.1 0.04 0.004
J 1.10 0.1 0.04 0.004
K 3.20 0.1 0.13 0.004
L 2.00 0.1 0.08 0.004
Mmax.5.5 0.2 max.0.22 0.008
N 30.40 0.4 1.20 0.016
O 15.00 0.2 0.59 0.008
P (A-Contact) 3.60 0.1 0.14 0.004
P (K-Contact) 3.30 0.1 0.13 0.004
Q 2.80 0.2 0.11 0.008
Dimension mm
tol.
(±mm) inches
tol.
(±inches)
A17.00 0.2 0.67 0.008
B 38.00 0.3 1.50 0.012
C 1.40 0.4 0.06 0.016
D 8.50 0.2 0.33 0.008
E 32.00 0.3 1.26 0.012
F 27.00 0.2 1.06 0.008
G1.5x45° 0.1 0.06x45° 0.004
H 20.32 0.2 0.80 0.008
I (A-Contact) 1.50 0.1 0.06 0.004
I (K-Contact) 1.10 0.1 0.04 0.004
J 1.10 0.1 0.04 0.004
K 3.20 0.1 0.13 0.004
L 2.00 0.1 0.08 0.004
Mmax.5.5 0.2 max.0.22 0.008
N 23.40 0.4 0.92 0.016
O 15.00 0.2 0.59 0.008
P (A-Contact) 3.60 0.1 0.14 0.004
P (K-Contact) 3.30 0.1 0.13 0.004
Q 2.80 0.2 0.11 0.008
FHR 2-3818
FHR 2-3025
Vishay Precision Group
Document No.: 63999
Revision: 27-Apr-11
www.vishaypg.com
1
Legal Disclaimer Notice
ALL PRODUCTS, PRODUCT SPECIFICATIONS AND DATA ARE SUBJECT TO CHANGE WITHOUT NOTICE.
Vishay Precision Group, Inc., its affiliates, agents, and employees, and all persons acting on its or their
behalf (collectively, “Vishay Precision Group”), disclaim any and all liability for any errors, inaccuracies or
incompleteness contained herein or in any other disclosure relating to any product.
The product specifications do not expand or otherwise modify Vishay Precision Group’s terms and conditions of
purchase, including but not limited to, the warranty expressed therein.
Vishay Precision Group makes no warranty, representation or guarantee other than as set forth in the terms
and conditions of purchase. To the maximum extent permitted by applicable law, Vishay Precision Group
disclaims (i) any and all liability arising out of the application or use of any product, (ii) any and all liability,
including without limitation special, consequential or incidental damages, and (iii) any and all implied
warranties, including warranties of fitness for particular purpose, non-infringement and merchantability.
Information provided in datasheets and/or specifications may vary from actual results in different applications
and performance may vary over time. Statements regarding the suitability of products for certain types of
applications are based on Vishay Precision Group’s knowledge of typical requirements that are often placed on
Vishay Precision Group products. It is the customer’s responsibility to validate that a particular product with the
properties described in the product specification is suitable for use in a particular application.
No license, express, implied, or otherwise, to any intellectual property rights is granted by this document, or by
any conduct of Vishay Precision Group.
The products shown herein are not designed for use in life-saving or life-sustaining applications unless otherwise
expressly indicated. Customers using or selling Vishay Precision Group products not expressly indicated for use
in such applications do so entirely at their own risk and agree to fully indemnify Vishay Precision Group for any
damages arising or resulting from such use or sale. Please contact authorized Vishay Precision Group personnel
to obtain written terms and conditions regarding products designed for such applications.
Product names and markings noted herein may be trademarks of their respective owners.
Legal Disclaimer Notice
Disclaimer
Document No.: 63999
Revision: 27-Apr-11