Parker IQAN-MC31 Instruction Book

28Diagnostic digital outputsInstruction book, IQANDiagnostic digital outputsThe IQAN-MC31 has two types of digital outputs. When used in pairs, high-side +low-side, diagnostics may be performed. DOUT A-E are the designations for the pairedDOUT channels. DOUT-A = DOUT-F (HS) + DOUT-K (LS) and so on. For currentratings on the DOUT’s, see Appendix A.Connecting loads to diagnostic digital outputsConnecting of loads to the digital outputs such as on/off valves is done by using theDOUT (HS)/DOUT (LS) paired positions.Protection against voltage transientsA clamping diode must be placed between the digital output (HS) and digital output(LS), as close to the load as possible. This reduces EMI, it also helps in protecting theoutput against high voltage transients. Use the diode:1N5408 (3A/1000V).Depending on the load, other clamping diodes might be used instead.DOUT output diagnosticsThe diagnostic DOUT is capable of detecting internal faults as well as wiring faults.The fault will be identified as one of the following status values in IQANdesign.• Over load (e.g. over current)• Open load (e.g. open circuit or under current)• "Error - internal error in the IQAN-MC31 power driverThe reported status is describing the most likely fault condition, but in certain cases thestatus will not match the actual fault. For details on failure modes, see Appendix B.There are faults that are detected on startup, and that will prevent the module fromstarting the application. These are all faults where an output is connected to +BAT onstartup.To detect these faults, it is important that all connectors are plugged-in before themodule is started. See section Start-up, also see Appendix B.EXAMPLEConnect the on/off valve to the digital output using the DOUT (HS) and the DOUT(LS) as return, respectively.Connecting a load to the diagnostic digital output.d1IQAN-MC31DOUT (LS)DOUT (HS)