Low Profile Aluminium
Housed Power Resistors
WCCHB / WCDH Series
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
General Note
TT electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT electronics’ own data and is considered accurate at time of going to print.
© TT electronics plc
09. 11
· Low profile aluminium casing
· Up to 1.8kW rating on heatsink
· Up to 900W rating without heatsink
· Excellent pulse load performance
· Ideal for dynamic braking in 2 - 30kW drives
· High isolation voltage of 3.5kV
· RoHS compliant, non-flammable construction
C
H
W
A
B
ΦD
Section types
1 2
Low Profile Aluminium Housed
Power Resistors
WCCHB / WCDH Series
Low profile aluminium casing
Up to 1.8kWrating on heatsink
Up to 900Wrating without heatsink
Excellent pulse load performance
Ideal for dynamic braking in 2 - 30kW drives
High isolation voltage of 3.5kV
RoHS compliant, non-flammable construction
Electrical Data WCDH600 WCCHB110 WCDH900 WCCHB166 WCDH1300 WCCHB216 WCCHB270 WCCHB320
Power rating (on 0.5°C/W heatsink) watts 600 650 900 950 1300 1400 1600 1800
Power rating (in free air) watts 250 300 400 480 550 600 770 900
Overload rating (5s, non-repetitive) watts 5,000 4,000 8,000 5,500 10,000 8,000 10,000 12,000
Resistance range ohms 2R2 - 200R 3R3 - 250R 3R3 - 300R4R7 -
390R5R1 -
470R
TCR ppm/°C 100
Resistance tolerance % 5, 10
Dielectric withstand (50Hz AC, 60s) kV rms 3.5
Insulation resistance (1kV)
ohms
>1G
Ambient temperature range °C -40 to +90
Physical Data
Dimensions in mm, weight in g
L
±1 P
±1 H
nom W
nom A
nom B
nom C
nom ΦD
nom Section
type Wt.
nom
WCDH600 102 81 12.5 68 57 45 9 5.5 2 195
WCCHB110 110 98 15 76 60 53 10.5 4.8 1 220
WCDH900 145 124 12.5 68 57 45 9 5.5 2 270
WCCHB166 166 154 15 76 60 53 10.5 4.8 1 350
WCDH1300 195 174 12.5 68 57 45 9 5.5 2 365
WCCHB216 216 204 15 76 60 53 10.5 4.8 1 480
WCCHB270 270 258 15 76 60 53 10.5 4.8 1 620
WCCHB320 320 2 x
154 15 76 60 53 10.5 4.8 1 790
Construction
A wirewound elementon an insulating support is held in the aluminium profile in a symmetrical manner toallow for
thermal expansion during high loads. An optional internal thermostat is fitted. The housing is then filled with quartz
sand, MgO or Al2O3 to spread the heat effectively and minimise surface temperature rise. The termination wires are
300mm long style 1659 PTFE cables, AWG18/16/14 in natural colour. Standard protection is IP45; IP56 is optional.
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyns own test data and is considered accurate at time of print.
Welwyn Components Limited
Welwyn Electronics Park, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 822181 Fax: 01670 829465 Web: www.welwyn-tt.com
Low Profile Aluminium Housed
Power Resistors
WCCHB / WCDH Series
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
General Note
TT electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT electronics’ own data and is considered accurate at time of going to print.
© TT electronics plc
09. 11
Low Profile Aluminium Housed Power Resistors
WCCHB / WCDH Series
Thermal and Overload Data
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyns own test data and is considered accurate at time of print.
Welwyn Components Limited
Welwyn Electronics Park, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 822181 Fax: 01670 829465 Web: www.welwyn-tt.com
Temperature Derating
0%
20%
40%
60%
80%
100%
120%
-40 -20 020 40 60 80 100
Ambient temperature (°C)
Proportion of Power Rating
Surface Temperature Rise
0
100
200
300
400
500
0% 50% 100% 150%
Proportion of Rated Power
Temperature Rise (°C)
Repetitive Overload (120s cycle, heatsink mounted)
0
2
4
6
8
10
12
14
1.0 10.0 100.0
Duration (s)
Po wer (kW )
600
650
900
950
1300
1400
1600
1800
Low Profile Aluminium Housed
Power Resistors
WCCHB / WCDH Series
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
General Note
TT electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT electronics’ own data and is considered accurate at time of going to print.
© TT electronics plc
09. 11
Low Profile Aluminium Housed Power Resistors
WCCHB / WCDH Series
Ordering Procedure
Example: WCDH900 with IP45 protection and a160°C thermostat at 100 ohms and 5% tolerance:
W C D H 9 0 0 A 160–100 R J B
Type
Protection degree
A IP45 Standard
B IP56
Thermostat option
NT No Thermostat
Temperature (°C) 160 standard
Value (use IEC62 code)
Tolerance (use IEC62 code)
J 5% K 10%
Packing
B Bulk Pack All sizes Box Standard
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability 01/10
All information is subject toWelwyns own test data and is considered accurate at time of print.
Welwyn Components Limited
Welwyn Electronics Park, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 822181 Fax: 01670 829465 Web: www.welwyn-tt.com