TRIPLEX T9431 DCS模塊卡件
1+TC使用余量)并存儲為A3學習數據\電機啟動\學習啟動容量。該熱容量裕度確保電機啟動成功。如果數字大于100%,則100%存儲為學習起動容量。成功的電機啟動是指相電流從0上升到大于過載拾取,然后在加速后下降到過載曲線拾取水平以下。如果啟動抑制功能啟用,則每次電機停止時,可用的熱容量(100%–使用的熱容量)與學習的啟動容量進行比較。如果可用的熱容量不超過學習的啟動容量,或不等于100%,則啟動抑制塊將激活,直到有足夠的熱容量。當發生阻塞時,鎖定時間將等于電機冷卻到可接受的啟動溫度所需的時間。該時間是S5熱模型\熱模型\冷卻時間常數停止設定值的函數。如果此功能被“關閉”,則在過載鎖定復位之前,所用熱容量必須降低至15%。如果負載因不同的起動而變化,則應關閉此功能。b) 示例:如果最后5次啟動的熱容量分別為24%、23%、27%、25%和21%,則學習啟動容量為27%×1.25=33.75%。如果電機在使用90%熱容量的情況下停止,將發出啟動塊。當電機冷卻且所用熱容量降至66%時,允許啟動。如果冷卻時間恒定停止設定點編程30分鐘,鎖定時間將等于:? 啟動禁止? [輸入]更多起動抑制塊:關閉范圍:打開,關閉TC已用余量:25%范圍:0至25%,step:1 ENTER ESCAPE?信息ESCAPE TCused TCused GE Power Management 469 Motor Management Relay 4-55 4 SETPOINT PROGRAMMING 4.8 S7 Motor STARTING 4 4.8.3 JOGGING BLOCK(點動塊)功能點動塊功能可用于防止操作員點動電機(快速連續進行多次啟動和停止)。它由兩個不同的元素組成:開始/小時和開始之間的時間。啟動/小時功能不能保證在一小時內允許一定數量的啟動或啟動嘗試;相反,它確保在一小時內不會超過一定數量的啟動嘗試。同樣,如果在最近一次啟動之后,“允許啟動之間的時間”已過,則“啟動之間的間隔”功能不保證允許再次啟動。相反,它確保了兩次啟動之間的最小時間。然而,如果第一次嘗試冷啟動由于堵塞而失敗,或者因為過程過載而需要很長時間,則熱模型可能會減少一小時內可以嘗試的啟動次數。
1 + TC USED MARGIN) and stored as A3 LEARNED DATA\MOTOR STARTING\LEARNED STARTING CAPACITY. This thermal capacity margin ensures that a motor start will be successful. If the number is greater than 100%, 100% is stored as LEARNED STARTING CAPACITY. A successful motor start is one in which phase current rises from 0 to greater than overload pickup and then, after acceleration, falls below the overload curve pickup level. If the Start Inhibit feature is enabled, each time the motor is stopped, the amount of thermal capacity available (100% – THERMAL CAPACITY USED) is compared to the LEARNED STARTING CAPACITY. If the thermal capacity available does not exceed the LEARNED STARTING CAPACITY, or is not equal to 100%, the Start Inhibit Block will become active until there is sufficient thermal capacity. When a block occurs, the lockout time will be equal to the time required for the motor to cool to an acceptable temperature for a start. This time will be a function of the S5 THERMAL MODEL\THERMAL MODEL\COOL TIME CONSTANT STOPPED setpoint. If this feature is turned "Off", the THERMAL CAPACITY USED must reduce to 15% before an overload lockout resets. This feature should be turned off if the load varies for different starts. b) EXAMPLE If the THERMAL CAPACITY USED for the last 5 starts is 24, 23, 27, 25, and 21% respectively, the LEARNED STARTING CAPACITY is 27% × 1.25 = 33.75% used. If the motor stops with 90% thermal capacity used, a start block will be issued. When the motor has cooled and the level of thermal capacity used has fallen to 66%, a start will be permitted. If the COOL TIME CONSTANT STOPPED setpoint is programmed for 30 minutes, the lockout time will be equal to: ? START INHIBIT ? [ENTER] for more START INHIBIT BLOCK: Off Range: On, Off TC USED MARGIN: 25% Range: 0 to 25%, step: 1 ENTER ESCAPE e e MESSAGE ESCAPE TCused TCused GE Power Management 469 Motor Management Relay 4-55 4 SETPOINT PROGRAMMING 4.8 S7 MOTOR STARTING 4 4.8.3 JOGGING BLOCK a) FUNCTION The Jogging Block feature may be used to prevent operators from jogging the motor (multiple starts and stops performed in rapid succession). It consists of two distinct elements: Starts/Hour and Time Between Starts. The Starts/Hour feature does not guarantee that a certain number of starts or start attempts will be allowed within an hour; rather, it ensures that a certain number of start attempts will not be exceeded within an hour. Similarly, the Time Between Starts feature does not guarantee another start will be permitted if the TIME BETWEEN STARTS PERMISSIBLE elapses after the most recent start. Rather, it ensures a minimum time between starts. If however, the first start attempt from cold is unsuccessful due to a jam or it takes long because the process is overloaded, the Thermal Model might reduce the number of starts that can be attempted within an hour.