ROWAN ELETTRONICA s.r.l. -ViaUgoFoscolo,20 - 36030CALDOGNO - VI - ITALY
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Descriptionof microswitch operationand set-up for the varioustypes of load
(inductive-resistive)withopen-loopcontrolboard.
Inthis case CODE 310S Regulator is set uptomanually regulate load voltage from zero to100%of line voltage.
Voltageatloadcanbeadjustedbypotentiometer,orbyDCsignalfrom0to10VderivedfromPLC,programmable
logic or other interface analog boards. If load insertions are frequent, it is convenient to use the starting contact
or open collector npn transistor (see controls terminal block 4-12 on page 6). Obviously the load is to be star or
delta-connected according to the value of the power supply line and to the load nameplate information.
Fans:INDUCTIVELOAD
CODE 310S actuation can be used to control the speed of fans driven by normal motors of unit power of up to
approximately 0.75kW. Its use with more powerful fans would cause normal motors to dangerously sustain
overcurrentatintermediatespeeds;thereforemore0.75kWfanscanbeconnectedinparallelchoosingactuation
setting that supports the overall power engaged. Typical use is in ventilation systems for industrial buildings or
shedsfor zootechnicalbreeding. Forfansgreater than0.-75kWitisadvisable toreplacethe normalmotorwitha
Rowantypeonewhicheliminatestheabove-mentionedinconveniencesorusingstandardDEFLATED motorsor
withSQUIRREL CAGE in SILUMIN.
In case of more fans connected in parallel with the possibility of group exclusion choose the open-loop voltage
operation mode with stabilized load voltage (see N°5 operation mode at page 8); in this way, it keeps the output
voltage stable even when the quantity of fans changes.
ElettricalResistance-Lamps:RESISTIVELOAD
CODE310Sactuatorcanbeusedtoregulatethetemperatureinhighpowerfurnaceschangingthevoltageatthe
electrical resistances wye-connected or delta-connected according to their supply voltage. In the 3-wire star
connectiontheloadmustbebalanced,otherwisewewouldhavedangerousovervoltageatthelowerpowerload
(voltageincreaseisproportionaltothepowerdifferenceoftheloadsconnectedtotheotherphases);byconnecting
theneutraltothewyecentreyoumayoperateevenwithunbalancedloadswithoutanyproblems(N°2OPERATION
MODE PAGE 8). With the load 6-wire delta-connected it is also possible to work with unbalanced loads. The
maximum power that may be applied to every single phase can be obtained from the actuator power divided by
3 (refer to the table on page 4). In case of 6-wire load connction the load power can be multiplied by 1.73.
Attention! sometimes it is necessary to adjust P4 all anti-clockwise to avoid that the load voltage gets 100%
without possibility to get back to zero volt.
Transformers-Alquist Motors-RowanMotors: INDUCTIVE LOAD
CODE310actuationmayalsobeusedtoregulatevoltageatthethree-phasetransformerprimary.Thisallowsits
applicationasAC/DClowvoltagepowersupplies,evenhighpowerones,withmanualregulationofoutputvoltage
with or without stabilization (see close loop voltage regulator).
NOTE:ForsomekindsofLoad, toavoid unbalancing of the line absorbtions near to the output max voltage, it is
necessary to OPEN micro S2 and adjust the Trimmer P4 all clockwise.
AnotherimportantapplicationofCODE310SactuationisvoltageregulationofALQUIST typeoperationmotors
(see setting N°7 on page 8).
LiketheRowanmotor,theAlquistmotoroperatesathighslips(evenwithblockedrotor),andwiththesamevoltage
atthestatorwindingsitstorqueincreasesasslipincreasesupto3timesthestartingtorque.Thepropertyofbeing
able to provide a sufficient area at constant power makes it particularly suitable in function as a winder in cases
where the ratio between the minimum and maximum diameter of the coil does not exceed 1/3. If the mechanical
systemhas agoodoutput efficiency(minimumfriction) thepullof thematerialto windwillremain constantasthe
coildiametervaries.Iftheratiobetweentheminimumdiameterandthemaximumdiameterofthecoilexceeds1/3
revert to servodiameter control system (like code 274S Rowan instrument).
Attention! Theuseof ROWANMOTORSinALQUISTMODEatfullvoltagecanbedoneonlyduringthestarting
phase inordertorapidlyacceleratein thepresence ofhighinertia.Thisvoltagevaluemustbelimited toa value
inconformitytoourdiagrams) necessarytokeepthecurrent(atlockedrotor)withinthemotorratedvaluereduced
of 15%.
