GE IC3645SR4T405CT1 Installation And Operation Manual

GE IC3645SR4T405CT1 Installation And Operation Manual Manual pdf 15 page image

DIAGNOSTIC STATUS CODESIT TRANSISTOR CONTROL Page 15January 20084.2.2.a Low-Level Signals (Level L)Low-level signals are designated as level L. Theseconsist of:• Analog signals 0 through ±15 V• Digital signals whose logic levels are less than 15V DC• 4 – 20 mA current loops• DC busses less than 15 V and 250 mAThe following are specific examples of level L signalsused in drive equipment cabling:• Control common tie• DC buses feeding sensitive analog or digitalhardware• All wiring connected to components associatedwith sensitive analog hardware with less than 5Vsignals (for example, potentiometers andtachometers)• Digital tachometers and resolvers• Dash display cabling• RS-232 cablingNote: Signal inputs to analog and digital blocksshould be run as shielded twisted-pair (for example,inputs from tachometers, potentiometers, and dashdisplays).4.2.2.b High-Level Signals (Level H)High-level signals are designated as level H. Thesesignals consist of:• Analog and digital signals greater than 15 V DCand less than 250 mAFor example, switch inputs connected to batteryvolts are examples of level H signals used in driveequipment cabling.4.2.2.c Medium-Power Signals (Level MP)Medium power signals are designated as level MP.These signals consist of:• DC switching signals greater than 15 V• Signals with currents greater than 250 mA andless than 10AThe following are specific examples of level MPsignals used in drive equipment cabling:• DC busses less than 10 A• Contactor coils less than 10 A• Machine fields less than 10 A4.2.2.d High Power Signals (Level HP)Power wiring is designated as level HP. This consistsof DC buses and motor wiring with currents greaterthan 10 A.The following are specific examples of level HPsignals used in drive equipment cabling:• Motor armature loops• DC outputs 10 A and above• Motor field loops 10 A and above4.2.3 Cable Spacing GuidelinesRecommended spacing (or clearance) betweencables (or wires) is dependent on the level of thewiring inside them. For correct level separation wheninstalling cable, the customer must apply the generalguidelines (section 4.2.3.a), outlined below.4.2.3.a General Cable SpacingThe following general practices should be used for alllevels of cabling:• All cables and wires of like signal levels andpower levels must be grouped together.• In general, different levels must run in separatewire bundles, as defined in the different classes,identified above. Intermixing cannot be allowed,unless noted by exception.• Interconnecting wire runs should carry a leveldesignation.• If wires are the same level and same type signal,group those wires from one location to any otherlocation together in multiconductor cables or bindthem together with twine or zip-ties.• When unlike signals must cross, cross them in90° angles at a maximum spacing. Where it isnot possible to maintain spacing, place agrounded steel barrier between unlike levels atthe crossover point.4.2.4 Cabling for Vehicle RetrofitsReducing electrical noise on vehicle retrofits requirescareful planning. Lower and higher levels shouldnever encircle each other or run parallel for longdistances.It is practical to use existing wire runs or trays as longas the level spacing (see section 4.2.2) can bemaintained for the full length of the run.Existing cables are generally of high voltage potentialand noise producing. Therefore, route levels L and Hin a path separate from existing cables, wheneverpossible. For level L wiring, use barriers in existingwire runs to minimize noise potential.