Short-time load and duty cycle

The performance data in this catalogue refers to the DB operating mode (continuous operation). For smaller load times AB (intermittent operation), in most cases a transformer of smaller type output can be used. The duty cycle ED for transformers is the ratio of the switch-on or load time to the cycle time. In order to avoid impermissible temperature increases, the maximum cycle duration of 10 minutes must not be exceeded (all this corresponds to a continuous operation).

The duty cycle is calculated as follows:
ED% = operating period: (Operating period + operating time) x 100%

The type power for short time load is calculated as follows:
Type power = rated power x √ED%: 100

It is to differentiate according to standard under the following operating modes:

S1: Continuous operation, constant load
S2: Short-time operation, constant load
S3: Intermittent operation without influence of the temperature rise
S4: Intermittent operation with influence of the temperature rise
S5: Intermittent operation with influence of starting and braking to the temperature
S6: Continuous operation with intermittent loading
S7: Continuous operation with start-up and braking
S8: Continuous operation with load change