Keysight Technologies B2900 Series, User Manual

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6-34 Keysight B2900 User’s Guide, Edition 5
Function Details
Over Temperature Protection
Over Temperature Protection
The over temperature protection is effective for preventing damage to a channel
from over temperature. If B2900 is used in an environment over 30

C, channel
outputs are limited to the value less than the maximum value. If a channel output
reaches the limit, all channels automatically and immediately set the output to 0 V
and set the output switch to off. And the causal channel is locked automatically.
To unlock the channel, the self-test must be performed. If the self-test does not
report any problem, you can use the channel soon. For performing the self-test, see
“Self-test” on page 3-11 .
The maximum output for the condition over 30

C is less than the maximum output
for the specification condition of 23

C

5

C. The channel output limit is given by
the following formula.
DC
MAX

( [ ( P
CS
+ 30
-
T
AMB
)
-
|V
OAB

I
B
| ] / |V
OAP

I
P
| )
2

100
The parameters are described below.
• DC
MAX
: Allowable maximum duty ratio in %, or 0 for DC bias output
• P
CS
: Maximum power, 64 W
• T
AMB
: Ambient temperature, in

C
• V
OAB
= 250 V, for |I
B
|

105 mA
V
OAB
= 39 V, for |I
B
| > 105 mA and |V
B
| > 6V
V
OAB
= 21 V, for |I
B
| > 105 mA and |V
B
|

6V
V
B
: Pulse base voltage setting value or DC bias voltage setting value, in V
• I
B
: Current at pulse base or DC current, in A
• V
OAP
= 250 V, for |I
P
|

105 mA
V
OAP
= 39 V, for |I
P
| > 105 mA and |V
P
| > 6V
V
OAP
= 21 V, for |I
P
| > 105 mA and |V
P
|

6V
V
P
: Pulse peak voltage setting value, in V
• I
P
: Current at pulse peak, in A