XBTZ908
如果循环重复减速，则必须考虑连续功率。如果循环时间长于吸收能量EB和连续功率PPR之比，则内部制动电阻足够。如果系统减速更频繁，则内部制动电阻不足。在此示例中，EB/PPR的比率为8.8 s。如果循环时间较短，则需要外部制动电阻器。额定外部制动电阻特性曲线用于额定制动电阻这两个特性也用于额定电机。拟考虑的特性曲线段由Di（D1…D3）指定。计算恒定减速时的能量时，必须知道总惯性Jt。。Jt=Jm+Jc Jm：电机惯量（带抱闸）Jc：负载惯量每个减速段的能量计算如下：计算段（D1）…（D3）：单位：Ei，单位为Ws（瓦特秒），Jt，单位为kgm2，ω，单位为rad，ni，单位为min-1。Engineering 0198441113767 2017年9月83日参见设备能量吸收Evar的技术数据（不考虑制动电阻）。在接下来的计算步骤中，仅考虑能量Ei超过设备能量吸收的那些段Di。这些多余能量EDi必须通过制动电阻器转移。使用以下公式计算EDi：EDi=Ei-Evar（单位：Ws）计算每个机器循环的连续功率Pc：单位：Pc in W，EDi in Ws和循环时间T in s。选择分两步进行： 如果满足以下条件，则内部制动电阻足够。 减速期间的大能量必须小于制动电阻可吸收的峰值能量：（EDi）<（ECr）。 不得超过内部制动电阻器的持续功率：（PC）<（PPr）。 如果不符合条件，则必须使用符合条件的外部制动电阻器。有关外部制动电阻器的订单数据，请参阅“附件和备件”一章（见第635页）

If the deceleration is repeated cyclically, the continuous power must be taken into account. If the cycle time is longer than the ratio of the energy to be absorbed EB and the continuous power PPR, the internal braking resistor is sufficient. If the system decelerates more frequently, the internal braking resistor is not sufficient. In this example, the ratio of EB/PPR is 8.8 s. An external braking resistor is required if the cycle time is shorter. Rating the External Braking Resistor Characteristic curves for rating the braking resistor These two characteristics are also used for the rating the motor. The segments of the characteristic curves to be considered are designated by Di (D1 ... D3). The total inertia Jt must be known for the calculation of the energy at constant deceleration.. Jt = Jm + Jc Jm: Motor inertia (with holding brake) Jc: Load inertia The energy for each deceleration segment is calculated as follows: Calculation for the segments (D1) … (D3): Units: Ei in Ws (wattseconds), Jt in kgm2, ω in rad and ni in min-1. Engineering 0198441113767 09/2017 83 See the technical data for the energy absorption Evar of the devices (without consideration of a braking resistor). In the next calculation steps, only consider those segments Di , whose energy Ei exceeds the energy absorption of the device. These excess energies EDi must be diverted by means of the braking resistor. EDi is calculated using the following formula: EDi = Ei - Evar (in Ws) The continuous power Pc is calculated for each machine cycle: Units: Pc in W, EDi in Ws and cycle time T in s The selection is made in two steps:  If the following conditions are met, the internal braking resistor is sufficient.  The maximum energy during deceleration must be less than the peak energy that the braking resistor can absorb: (EDi)<(ECr).  The continuous power of the internal braking resistor must not be exceeded: (PC)<(PPr).  If the conditions are not met, you must use an external braking resistor that meets the conditions. For order data for the external braking resistors, see chapter Accessories and Spare Parts (see page 635)