繼電器是液壓貨梯http://www.manetech.cn/上的重要部件之一，長期使用也會出現失效的狀況，就會嚴重影響液壓貨梯的正常工作。那么如何判斷液壓貨梯繼電器是否失效呢?
　　
1、液壓貨梯繼電器線圈通電時不動作。
Hydraulic freight elevator does not move when the relay coil is energized.
　
2、液壓貨梯繼電器線圈斷電時不返回。
Hydraulic freight elevator does not return when the relay coil is de-energized.
　　
3、液壓貨梯觸點發生熔接或其他形式的粘接。
Welding or other forms of bonding hydraulic freight elevators contacts occur.

4、液壓貨梯閉合觸點的接觸壓降超過其規定范圍內的極限值。
Hydraulic freight elevator closed contact contact pressure drop exceeds its limit within a predetermined range.
　
5、液壓貨梯http://www.manetech.cn/試品零部件有破壞性損壞，連接導線及零部件松動。
Hydraulic freight elevators destructive damage to parts of the test, the connection wires and loose components.