These braking resistors are designe

These braking resistors are designed for applications which occasionally require a high braking power,
e.g. for emergency stopping. The braking resistor stores the braking energy generated and heats up as a
result. The resistor can store an energy value W corresponding to power P20 for 20 seconds.
Approximately the same energy is produced if the resistor is loaded with power P3 according to the time
characteristic shown below. After this type of load is applied, the thermal storage capacity of the resistor
is exhausted.
The braking resistor can only slowly release the stored energy (heat) to the environment. The drive must
be planned in such a way that a no-load pause appropriate to the braking resistor used is maintained
according to the following diagram.
Before the resistor is loaded again with P20 or P3, it must be allowed to cool down to ambient
temperature again. This state is reached after an interval corresponding to about 4 times the thermal
time constant τ.
P20
P3
t
Braking
power
T 3s 20s 23s T+20s
W = P20 x 20s
T = 120 min
A temperature switch is mounted on the resistor. This responds if the ambient temperature is so high that
the resistor is thermally overloaded. The temperature switch cannot protect the resistor if it overheats as
a result of prolonged braking with P3 or P20! Reason: There is a long delay before the surface
temperature reaches the internal temperature of the resistor, i.e. the temperature switch detects the
overload too late. The overloaded resistor reaches a high ohmic value due to an internal protective
mechanism and must then be replaced. Tables 1 and 2 apply when the braking resistor is loaded with
continuous power.
The surface temperature exceeds the response temperature of the switch as a function of load. In this
case, the switch must be unscrewed from the resistor and replaced if necessary by a switch with a higher
response temperature.

結果 (中文) 3:

这些制动电阻的设计偶尔需要高制动功率的应用程序，
如紧急停车。制动电阻制动产生的能量储存和加热作为一种
结果。电阻可以存储相应的功率W P20 20秒的能量值。
大致相同的能量如果电阻负载功率P3根据特征如下所示的时间
产生。在应用这种类型的负载，电阻的热容量
殆尽。
制动电阻只能慢慢释放储存的能量（热量）的环境。驱动器必须
计划在这样一种方式，适当的制动电阻使用空载停顿是根据以下图保持
。
在电阻加载了P20或P3，它必须允许冷却下来的环境
温度。这种状态是对应于约4倍的热时间常数τ
区间后得出的。
P20
P3
T
制动
功率
3S 20 20
23S T TW = P20 x 20
t = 120分钟
温度开关安装在电阻。这种反应如果环境温度太高，
电阻热负荷。温度开关不能保护电阻是否过热是由于长时间
P3或P20制动！原因：有表面
温度达到电阻内部的温度在长时间的延迟，即E.温度开关检测
过载太晚。重载的电阻达到由于内部保护
机制高欧姆值，必须更换。表1和表2申请当制动电阻负载
连续功率。
表面温度超过开关的响应温度随负荷。在这
案例，开关必须把电阻代替如果由一个更高的
反应温度开关必要。