Guidelines for planning the electrical installation 85Implementing a bypass connectionAn application-engineered bypass connection is available from ABB. For moreinformation, see Bypass connection for ACS880-07, -17, -37 (40...1200 A) optiondescription (3AXD50000048959 [English]).WARNING! Never connect the drive output to the electrical power network. Theconnection may damage the drive.Protecting the contacts of relay outputsInductive loads (relays, contactors, motors) cause voltage transients when switched off.The relay contacts on the drive control unit are protected with varistors (250 V) againstovervoltage peaks. In spite of this, it is highly recommended that inductive loads areequipped with noise attenuating circuits (varistors, RC filters [AC] or diodes [DC]) in orderto minimize the EMC emission at switch-off. If not suppressed, the disturbances mayconnect capacitively or inductively to other conductors in the control cable and form a riskof malfunction in other parts of the system.Install the protective component as close to the inductive load as possible. Do not installprotective components at the relay outputs.1) Relay outputs; 2) Varistor; 3) RC filter; 4) diode123230 V AC+ 24 V DC4230 V AC
