Carrier AquaEdge 19XRV series Operation, Maintenance And Installation Manual

Also see for AquaEdge 19XRV series: Start-up, operation and maintenance instructions Start-up and service instructions Installation instructions Start-up, operation and maintenance instructions Start-up and service instructions

Contents

76Fine Tuning VPF Surge Prevention — Figures 41-44 showhow the parameters defined below will affect the configuredsurge line.NOTE: Before tuning surge prevention check for VFD speedlimitation or capacity overrides. If the source of low capacity isfound in one of these places, do not proceed with an attempt totune the Surge Prevention configurations.If capacity is not reachedand1. ACTUAL GUIDE VANE POSITION < GUIDE VANETRAVEL RANGEand2. SURGE PREVENTION ACTIVE = YESand3. PERCENT LINE CURRENT < 100%then the surge line is probably too conservative.Note the following parameters from ICVC when maximumAVERAGE LINE CURRENT achieved:• EVAPORATOR REFRIGERANT TEMP• EVAPORATOR PRESSURE• CONDENSER REFRIG TEMP• CONDENSER PRESSURE• ACTUAL GUIDE VANE POSITION• AVERAGE LINE CURRENTThe ACTIVE DELTA Tsat and the SURGE LINE DELTATSAT can be monitored on the VPF_STAT screen. When DEL-TA TSAT exceeds SURGE LINE DELTA TSAT surge preven-tion will occur.If ACTUAL GUIDE VANE POSITION is less than 30%,then increase SURGE/HGBP DELTA TSMIN in steps of 2º Funtil one of the three conditions listed above no longer applies.Do not change SURGE/HGBP DELTA TSMAX.If ACTUAL GUIDE VANE POSITION is greater than60%, then increase SURGE/HGBP DELTA TSMAX in steps of2º F until cooling capacity is reached or one of conditions listedabove no longer applies. Do not change SURGE/HGBP DEL-TA TSMIN.If ACTUAL GUIDE VANE POSITION is more than 30%AND less than 60%, then:1. Increase SURGE/HGBP DELTA TSMIN in steps of 2º F.2. Increase SURGE/HGBP DELTA TSMAX in steps of 2ºF.3. Repeat Steps 1 and 2 until one of the conditions listedabove no longer applies.NOTE: DELTA TSMIN should seldom need to be increasedmore than 10 degrees above the selection program value. Like-wise, DELTA TSMAX rarely requires more than a 2 degreeincrease.If surge is encountered then the surge line is probably toooptimistic or high. Note following parameters from ICVC atsurge:• EVAPORATOR REFRIGERANT TEMP• EVAPORATOR PRESSURE• CONDENSER REFRIG TEMP• CONDENSER PRESSURE• ACTUAL GUIDE VANE POSITION• AVERAGE LINE CURRENTIf ACTUAL GUIDE VANE POSITION is less than 30%,go to Step 1. If ACTUAL GUIDE VANE POSITION is greaterthan 60%, then go to Step 3.1. Do not change SURGE LINE SHAPE FACTOR from thevalue selected by Chiller Builder (ECAT). DecreaseSURGE/HGBP DELTA TSMIN in 1° F steps up to 5times. Monitor chiller for surge.2. If ACTUAL GUIDE VANE POSITION is still less than30 and step 1 failed, then increase the value of SURGELINE SHAPE FACTOR in steps of 0.01 up to 2 times. Forexample, if surge is encountered when shape factor is –0.06, increase the SURGE LINE SHAPE FACTOR to –0.05. If this does not solve the problem, go to Step 5, evenif ACTUAL GUIDE VANE POSITION is less than 30%.3. Do not change SURGE LINE SHAPE FACTOR from thevalue selected by Chiller Builder (ECAT). DecreaseSURGE/HGBP DELTA TSMAX by 1°F Steps up to 5times. Monitor chiller for surge.4. If ACTUAL GUIDE VANE POSITION is greater than60% and Step 3 failed to eliminate surge, then setSURGE/HGBP DELTA TSMAX to 5° F below the valuespecified by Chiller Builder (ECAT). Increase the valueof the SURGE LINE SHAPE FACTOR in steps of 0.01 upto 2 times. For example, if surge is encountered when theSURGE LINE SHAPE FACTOR is –0.06, increase theSURGE LINE SHAPE FACTOR to –0.05. If this does notsolve the problem, go to Step 5, even if ACTUALGUIDE VANE POSITION is greater than 60%.5. If ACTUAL GUIDE VANE POSITION is greater than30% but less than 60% or if Step 2 failed (with ACTU-AL GUIDE VANE POSITION less than 30) or if Step4 failed (with ACTUAL GUIDE VANE POSITION0.005.0010.0015.0020.0025.0030.0035.0040.0045.0050.0055.0060.000 10 20 30 40 50 60 70 80 90 100 110Shape factor= -0.020Shape factor= -0.040Shape factor= -0.050GV_POSDelta TsatFig. 43 — Effect of SURGE LINE SHAPE FACTORon Surge Preventiona19-196105101520253035400 10 20 30 40 50 60 70 80 90 100 110Speed Factor=1.60Speed Factor=1.85Speed Factor=2.00GV_POSDelta TsatFig. 44 — Effect of SURGE LINE SPEED FACTORon Surge Preventiona19-1962