GRE3

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Vishay Milwaukee

Revision: 03-May-17

5

Document Number: 31882

THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT

DERATING CURVE

TEMPERATURE RISE OVER AMBIENT

Standard GRE3Jxxxxx 30 000 W grid banks are rated with max. design temperature rise of 375 °C over an ambient.

Continuous Duty Application with Constant Voltage Applied to Resistor

Solid line - GRE3J100R0K00N0000 standard 30 000 W, 100

Ω resistor bank

Dotted line - GRE3JR1000K00N0000 standard 30 000 W, 0.1

Ω resistor bank

Graph shows the peak element temperature is reached between 100 s and 400 s depending on active mass of material used to achieve

the desired resistance. Different rates of heating occur depending on the active mass used in the design.

Pulse Application with Non-Constant Voltage Applied to Resistor

Dashed line - GRE3JR1000K00N0000 standard 30 000 W, 0.1

Ω resistor bank

Graph shows the peak element temperature of about 450 °C over ambient is reached with an average continuous duty temperature

of 375 °C over ambient when a continuous voltage 0.5 MJ energy pulse is applied to the resistor for 5 s once every minute, cycled

continuously. Average temperature at continuous cycling is 375 °C (peaks above and below).

MATERIAL SPECIFICATIONS

Plate element

Stainless steel

Insulators

Ceramica/ alumina / mica

Mounting frame

Mill galvanized steel (stainless steel available upon request)

AMBIENT TEMPERATURE IN °C

120

0

100

80

60

40

20

-20

40

100

160

220

280

340

460

415

0

TIME IN s

500

0

400

300

200

100

50

100

150

200

250

300

350

30 000 W, 0.1

Ω cont. duty

30 000 W, 0.1

Ω pulsed with 1.5 MJ

30 000 W, 100.0

Ω cont. duty