Sigma-II Series SGM*H/SGDH USER'S MANUAL - Esco Drives ...

5.6 Flexible Cables5.6 Flexible Cables(1) Life of Flexible CableThe flexible cable supports 10,000,000 or more operations of bending life with the recommended bending radiusR = 90 mm (3.54 in) under the following test conditions.• Conditions1. Repeat moving one end of the cable forward and backward for 320 mm (12.60 in) with using the testequipment shown in the following.2. Connect the lead wires in parallel, and count the number of cable return motion times until a lead wire isdisconnected. Note that one reciprocating is counted as one test.Shifting distance 320 mm (12.60 in)Shifting endBendingradiusR=90 mm(3.54 in)Fixed endNote: 1. The life of flexible cable differs largely depending on the amount of mechanical shocks,mounting to the cable, and fixing methods. The life of flexible cable is limited under thespecified conditions.2. The life of flexible cable indicates the number of bending times in which lead wires areelectrically conducted and by which no cracks and damages that affects the performanceof cable sheathing are caused. Disconnecting the shield wire is not taken into account.5(2) Wiring PrecautionsEven if the recommended bending radius R is respected in the mechanical design, incorrect wiring may cause theearly disconnection. Observe the following precautions when wiring.(a) Cable twistingStraighten the flexible cables wiring.Twisted cables causes the early disconnection. Check the indication on the cable surface to make sure thatthe cable is not twisted.(b) Fixing methodDo not fix the moving points of the flexible cable, or stress on the fixed points may cause early disconnection.Fix the cable at the minimum number of points.(c) Cable lengthIf the cable length is too long, it may cause the cable’s sagging. Besides the cable length is too short, it maycause the excessive tension on the fixed points that will cause the early disconnection. Use a flexible cablewith the optimum length.(d) Interference between cablesAvoid interference between cables.Interference limits the motion of flexible cable, which causes early disconnection. Keep enough distancebetween cables, or provide a partition when wiring.5-59