Mecc Alte DSR Quick start guide

Guida Tecnica:
Regolatore Digitale DSR
Technical Guide:
DSR Digital Regulator
E309573

Instruction Manual DSR digital regulator - rev. 05 - pag. 2
INDEX pag. 2
INTRODUCTION pag. 3
MAIN CHARACTERISTICS pag. 3
1. Architecture of the system pag. 3
1.1 Regulator pag. 3
1.2 Communications module pag. 3
2. Technical characteristics pag. 3
3. Inputs and Outputs: technical specifications pag. 4
4. Block diagram pag. 5
INSTALLATION pag. 5
1. Overall dimensions drawings pag. 5
2. Connections pag. 6
3. Terminals pag. 6
4. DSR connections for typical applications pag. 6
5. Setting up the regulator pag. 6
5.1 Alternator voltage signals pag. 6
5.2 Calibrating sensing pag. 6
5.3 50/60 Signal pag. 6
6. Serial communications pag. 10
7. APO Contact pag. 10
8. VOLT, STAB,Hz and AMP Trimmers pag. 10
9. Vext Input pag. 10
SERIAL CONNECTION pag. 11
PARAMETERS AND OPERATING DATA pag. 12
1. ModBus registry list pag. 12
2. Word of configuration (Parameter P[10]) pag. 13
3.      pag. 13
4.Volatile memory addresses pag. 14
5. Fourth Status Word (Location L[39]) pag. 14
SETTING OF VOLT, STAB, AMP and Hz PARAMETERS pag. 15
1. Voltage pag. 15
1.1 Setting voltage pag. 15
1.2 Slow voltage variations pag. 15
2. Stability pag. 16
2.1 Adjustment of stability pag. 16
3. Excitation overcurrent pag. 20
3.1 Description pag. 20
3.2 Calibration with a supervision unit pag. 20
3.3 Calibration without a supervision unit pag. 21
4. Underspeed pag. 21
4.1 Description pag. 21
4.2 Calibration with a supervision unit pag. 21
4.3 Calibration without a supervision unit pag. 22
5. Overspeed pag. 22
6. Other parameters pag. 22
6.1 Vout / Vaux Ratio pag. 22
6.2 V/F slope at start up pag. 23
6.3 Short cirrcuit time pag. 23
CONTROLLING OF REGULATOR ALARMS pag. 23
1. Table of recapitulation pag. 23
2. Alarm signals with the indicator lights pag. 23
3. Description of alarms pag. 24
4. APO Output pag. 25
5. Board operation time pag. 25
DI1 COMMUNICATIONS UNIT pag. 26
1. Description pag. 26
2. Inputs and Outputs pag. 27
3. Powering DI1 pag. 28
USE OF PROGRAMMING SOFT. AND MONITORING OF THE DSR TERMINAL pag. 29
1. Installation pag. 29
2. Introduction pag. 29
3. Description of function pag. 30
4. Setting Files pag. 31
APPENDIX A pag. 34
APPENDIX B pag. 37

Instruction Manual DSR digital regulator - rev. 05 - pag. 3
The information contained in this manual may be modified without advance notice.
This revision supersedes and replaces all previous editions.
Even partial reproduction of this manual is prohibited, with any means whatsoever, without prior written au-
thorisation by Mecc Alte S.p.A.
INTRODUCTION
This manual contains information on the operation and use of the DSR digital regulator.
MAIN CHARACTERISTICS
1. Architecture of the system
The DSR is a voltage regulator for synchronous alternators, designed for stand alone working and calibra-
tion; to maximize performance, the regulator should be understood as part of a system made up of at least
three components: the DSR (control unit), a communications module (DI1, for example) and a supervision
unit, as illustrated in figure 4 or 12.
The connectors for connection to and from the power generator and communications module are located
on the DSR regulator.
The supervision unit can be made up of a personal computer, another “synoptic” device or both; it does
not have the function of controlling the system in real time, but allows programming and visualisation of all
operational parameters of the DSR.
If it is equipped with an RS485 or RS232 serial interface, the DI1 communications module is necessary for
its connection.
1.1 Regulator
Since the regulator is designed to control many different types of generators, it must be appropriately con-
figured to obtain the best performance; most of the settings are stored in a non-volatile integrated memory
(EEPROM). The first time the regulator is turned on, a default configuration will be present, which satisfies
the most widely requested characteristics and is suitable to facilitate installation: the trimmers are active
and the inputs for the external potentiometer and the 60 Hz jumper are enabled, therefore the basic cali-
brations can be performed without the use of additional equipment.
The regulator is available in two versions called DSR and DSR/A, the first is the standard one, optimized
for Mecc Alte alternators from series 3 to 38, the second is optimized for Mecc Alte alternators series 40-
46; the two versions differ mainly in some default parameters.
NOTE: the parameter that defines the output voltage (with the VOLT trimmer disabled) is set on 0 (so that
the adjustment takes place on the minimum voltage)
1.2 Communications module
The DI1 communications module (which is provided for connection to the COM connector of the DSR) is
equipped with a RS232 port and a RS485 port, through which it is possible to set the parameters (for both
configuration and operation) and “monitor” operation of the generator.
2. Technical Characteristics
• Full digital controlled regulator, based on DSP
• On-board machine installation
• Suitable for all self-regulated alternators
• Voltage supply: 40Vac÷270Vac (from auxiliary winding, output voltage or PMG)
• Frequency range: 12Hz ÷ 72Hz
• “Sensing” of voltage with true rms or average measurement (70÷280 Vac)
• Maximum continuous output current: 4Adc;
• Precision of voltage regulation: ± 1% from no-load to nominal load in static condition, with any power
factor and for frequency variations ranging from -5% to +20% of the nominal value.
In order to avoid damage to persons and/or property, only qualified personnel, having full
knowledge and understanding of the information contained in this manual, should perform the
procedures described herein; when power to the unit is on, the voltage present may be lethal for
the operator.
All connections must be made with the power off.
The plastic protections on connectors J1 and J2 must not be removed for any reason whatsoever.

Instruction Manual DSR digital regulator - rev. 05 - pag. 4
• Precision of voltage regulation: ± 1% from no-load to nominal load in static condition, with any power
factor and for frequency variations ranging from -5% to +20% of the nominal value.
• Transient power drops and overvoltage within ± 15%
• Voltage recovery time within ± 3% of the value set, in less than 300 msec.
• Transient overvoltage during start up: less than 5% of nominal voltage.
• Single phase sensing
• Parameters: VOLT, STAB, AMP and Hz can be set with trimmers (default) 50/60Hz through a
“jumper” (default); all parameters can be programmed via software.
• Analogical remote control of output voltage is possible through external voltage (0÷2,5Vdc) or with a
10 Kohm linear potentiometer.
• Environmental temperature: -25°C ÷ +70°C
• Underspeed protection with adjustable threshold and slope
• Overvoltage and undervoltage alarms
• Excitation overcurrent protection with delayed intervention
• Management of temporary short circuits (start up of asynchronous motors)
• Open collector output (not insulated) signalling intervention of protective devices (insulation on optional
DI1 module) with programmable activation with respect to the individual alarms and the possibility to de-
lay intervention.
• Abnormal operation conditions storage (type of alarm, number of events, duration of the last event, total
time)
• Memorization of the regulator operation time (starting from revision 11 of the Firmware)
• RS232 and RS485 serial communications interface (with optional DI1 module)
WARNING : Operation of the DSR is not specified below 12 Hz.
3. Inputs and Outputs: technical specifications
TABLE 1 : CONNECTOR CN1

 
  FunctionSpecifications Notes
1 Exc- Excitation Continuous Rating: 4Adc
Transitory Rating: 12Adc at peak
2 Aux/Exc+
3 Aux/Exc+ Power Frequency: from 12Hz to 72Hz
Range: 40Vac - 270Vac
9 Aux/Neutral
4 F_phase Range: 140Vac - 280Vac
Burden: <1VA Measurement of average value
(rectified) or actual effective va
lue for voltage adjustment
5 F_Phase
6 H_phase Range: 70Vac - 140Vac
Burden: <1VA
7 H_phase
8 Aux/Neutral
10 Vext/Pext Input for remote
voltage control
Type: Not insulated
Range: 0 - 2,5 Vdc or 10K Potentiometer
Adjustment: from – 14% to + 14%
(3)
Burden: 0 - 2 mA (sink)
Max length: 30m
(2)
Tolerates voltages from - 5V to
+ 5V but for values exceeding
the range it is automatically
disabled
11 Common
12 50/60Hz
50/60 Hz
Jumper Input Type: Not insulated Max length: 3m
Selection of underspeed
protection threshold 50·(100%-
Hz%) or 60·(100%-Hz%)
Hz% is the position relative to
the Hz trimmer or the
percentage value of parameter
21
13 Common
14 A.P.O. Active
protections output
Type: Non-insulated open collector
Current : 100mA
Voltage: 30V
Max length: 30m
(2)
Both activating alarm and
delay time are programmable
15 Common
Sensing
NOTE (1) The terminals are connected to each other on the board: 2 with 3, 4 with 5, 6 with 7, 8 with 9, 11 with 13 and 15.
NOTE (2) With external EMI filter SDR 128/K, see Fig.10 (3m without EMI filter)
NOTE (3) Starting from revision 10 of the Firmware. It is convenient do not exceed ±10%

Instruction Manual DSR digital regulator - rev. 05 - pag. 5
4. Block diagram
INSTALLATION
Upon receipt of the digital regulator, perform a visual inspection to ensure that no damage has been su-
stained during transportation and movement of the equipment. In the event of damage, advise the shipper,
the insurance company, the seller or Mecc Alte immediately. If the regulator is not installed immediately,
store it in its original packaging in a dust and humidity-free environment.
The regulator is normally installed in the generator terminal box. It is fixed with two M4x20 or M4x25
screws and must be installed in a location where the temperature does not exceed the environmental con-
ditions foreseen.
1. Overall dimensions drawings
dimensioni in mm
Name Function Notes
VOLT Voltage Calibration From 70Vac to 140Vac or from 140Vac to
280Vac, see paragraph “Setting the voltage”
STAB Calibration of dynamic response Adjustment of proportional gain, see paragraph
on “Stability”
Hz Calibration of underspeed protection
intervention threshold Variation up to -20% with respect to the nominal speed value set in jumper/parameter 50/60.
AMP Calibration of excitation overcurrent
protection
See paragraph “Calibration of excitation overcurrent
protection”
TABLE 2 : TRIMMERS
fig. 1
fig. 2

Instruction Manual DSR digital regulator - rev. 05 - pag. 6
2. Connections
The digital regulator connections depend on the application and excitation system.
Figure 1 shows the functional aspect of the connection points to the regulator.
3. Terminals
Figures 2 show the connection terminals; the connections must be made using cables having a minimum
diameter :
• for power cables on terminals 1, 2, 3 and 9 (Exc-, Aux/exc+, Aux): 1,5 mm²
• for signal cables: 0,5 mm²
4. DSR connections for typical applications
Drawings SCC0059/02, SCC0060/02, SCC0061/02, SCC0062/02, SCC0063/02, SCC0064/02 show DSR
regulator connections for typical applications.
Drawing SCC0059/02 shows the connection to Series 3 alternators with 6 terminals.
Drawing SCC0060/02 shows the connection to Series 3 alternators with 12 terminals.
Drawing SCC0061/02 shows the connection to alternators with 6 terminals with reference from 140V to
280V. Drawing SCC0062/02 shows the connection to alternators with 12 terminals, with reference to the
half phase from 70V to 140V (for example series ECO28-38, ECO40-1S, ECO40-2S, ECO40-1L, ECO40-
2L and ECO40VL)
Drawing SCC0063/02 shows the connection to alternators with 12 terminals, in series star connection or
series delta connection, with reference to the entire phase from 140V to 280V (for example series ECO28-
38, ECO40-1S, ECO40-2S ECO40-1L, ECO40-2L and ECO40VL)
Drawing SCC0064/02 shows the connection to alternators with 12 terminals, with reference to the half
phase from 140V to 280V (for example ECO40-3S, ECO40-1,5L, Series ECO43-46)
5. Setting up the regulator
Selection of the sensing scale takes place directly according to the connection on the power terminal
board; additional settings can be made with 4 trimmers (VOLT, STAB, AMP and Hz) and 3 jumpers
(50/60Hz, JP1 and JP2); the output voltage can also be set with an external analogical or numeric signal;
additional settings, can be made by modifying the 23 parameters stored in a non volatile integrated memo-
ry.
5.1 Alternator voltage signals
Terminals 4, 5, 6, 7 and 8 of connector CN1 are used for voltage sensing.
5.2 Calibrating sensing
A supplementary calibration may be necessary to compensate for any existing tolerances on analogical
voltage acquisition channels; in this case follow the procedure illustrated below:
1. Write 16384 on location 19
2. Disable the Trimmers (from the Configuration Menu)
3. Disable Vext (from the Configuration Menu)
4. Set the adjustment on the average or effective value (from the Configuration Menu)
5. Measure the voltage with a suitable instrument for the type of adjustment made (average value or rms
value)
6. Set the value at location 5 (or 6) until the voltage value, measured with the instrument, reaches 210 V (if
the sensing is connected to terminals 4 or 5) or 105V (if the sensing is connected to terminals 6 or 7),
keeping in mind that an increase in the value set provokes an increase in adjusted voltage and vicever-
sa.
7. In order to ensure that the value of voltage (available also at location 36) is the same as the value
measured at point 6, calibrate the data at location 7, reading the value in the first “STATUS” box (ref.
DSR Terminal Software).
8. Enable the trimmers you want to be active (from the Configuration Menu)
9. Enable Vext (from the Configuration Menu) if you want to be active
5.3 50/60 Signal
A jumper is located on the 50/60 input (connector CN1, terminals 12 and 13); if enabled from the
Configuration Menu, it provokes the commutation of the underspeed protection threshold from 50·(100%-
Hz%) to 60·(100%-Hz%), where Hz% represents the position relative to the Hz trimmer or the
percentage value entered in location 21 (where 10% corresponds to 16384).
An error in connection may have serious consequences for the unit.
Carefully check to make sure that all connections are precise and in accordance with the atta-
ched drawings, before turning on the power.

Instruction Manual DSR digital regulator - rev. 05 - pag. 7
Series 3 alternators with 6 terminals
Reference from 140V to 280V
Drawing SCC0059/02
Drawing SCC0060/02
Series 3 alternators with 12 terminals
Reference from 70V to 140V

Instruction Manual DSR digital regulator - rev. 05 - pag. 8
Series ECO alternators with 6 terminals
Reference from 140V to 280V
Alternators with 12 terminals, with reference on half phase, from 70V to 140V
Drawing SCC0061/02
DrawingSCC0062/01

Instruction Manual DSR digital regulator - rev. 05 - pag. 9
Drawing SCC0063/02
Alternators with 12 terminals, with reference on entire phase from 140V to 280V
Drawing SCC0064/02
Alternators 12 terminals, with reference on half phase from 140V to 280V

Instruction Manual DSR digital regulator - rev. 05 - pag. 10
Figure 3a: without saturation of the output voltage
upon reaching the input voltage limits
Figure 3b: with saturation of the output voltage
upon reaching the input voltage limits
6. Serial communications
The DI1 communications module (which is provided for connection to the COM connector of the DSR) is
equipped with a RS232 port and a RS485 port, through which it is possible to set the parameters (for both
configuration and operation) and monitor operation of the generator.
7. APO Contact
The acronym APO stands for Active Protection Output: (connector CN1 – terminals 14 and 15) 30V-
100mA non-insulated open collector transistor, normally opened, is closed (with a delay that can be
programmed from 1 to 15 seconds) when, among all the alarms, one or more of the active ones can be
selected separately.
8. VOLT, STAB, Hz and AMP Trimmers
The trimmers are enabled by the software from the Configuration Menu; if they are not enabled, they DO
NOT perform any function.
The VOLT trimmer allows adjustment from about 70V to about 140V or from about 140V to about 280V.
The STAB trimmer adjusts the dynamic response (statism) of the alternator under transient conditions.
The Hz trimmer allows a variation up to - 20% with respect to the nominal speed value set by jumper 50/60
(if it is active) or from box 50/60 of the Configuration Menu (at 50 Hz the threshold can be calibrated from
40 Hz to 50 Hz, at 60 Hz the threshold can be calibrated from 48 Hz to 60 Hz).
The AMP trimmer adjusts the excitation overcurrent protection intervention threshold.
9. Vext Input
The Vext input (connector CN1 – terminals 10 and 11) permits analogical remote control of output voltage
through a 10Kohm potentiometer with a programmable variation range through parameter 16 with respect
to the value set (by default the setting is ±14% starting from revision 10 of the Firmware); if you want to
use continuous voltage, it will be effective if it is in the range between 0V and +2,5V. The input tolerates
voltages from -5V to +5V, but for values exceeding the limits of 0V / +2,5V (or in the event of
disconnection), two options are possible: not to take the set point of external input (default configuration)
and return to regulation to the voltage value set with the trimmer (if enabled) or with parameter P[19], or
keep the minimum (or maximum) value of voltage that can be reached (see figures 3a and 3b). The two
options can be set with the RAM Voltage CTRL flag in the configuration menu corresponding to the bit
B7 of the configuration word P[10] (see PARAMETERS AND OPERATIONAL DATA - Para. 2). The setting
relative to the Vext input are summarised in table 5.
NOTE: the source of DC voltage must be capable of absorbing at least 2 mA.
In making adjustments it is reccomended not to exceed the nominal value of voltage of the alternator be-
yond ± 10%.
Relationship between analogical input (Vext) and output voltage (Vo)

Instruction Manual DSR digital regulator - rev. 05 - pag. 11
SERIAL CONNECTION
The COM connector is RESERVED for connection to the Dl1 communications module with the special ca-
ble provided with the module itself.
The serial interface of the Dl1 communications unit is of the RS232 or RS485 type: it will therefore be pos-
sible to connect several DSR-Dl1 groups as well (and therefore several generators) in parallel on the same
485 Bus, in order to monitor the operation with a single supervising unit. The regulator implements a sub-
system of the MODBUS standard for communications; the DI1-DSR set performs slave operation, whose
address is memorised in the EEPROM and is set during the phase of configuration.
When necessary, the DI1 interface permits insertion of the regulator in a RS485 network with other regula-
tors or other devices of a different type, but with the same type of bus. Detailed descriptions of the Mod-
Bus commands implemented are into the Technical Guide “Digital Regulators Comunication Protocol”
available on the web site www.meccalte.com
The “Master Unit” is made up of a PC or other dedicated equipment and can access the parameters and
functions of the regulator.
The master unit has the following possible functions:
• Repetition, or visualisation, of the generator status variables, even from a remote location
• Setting of single parameters
• Uploading and downloading of settings files
• Status readings (alarms, measuring variables)
• Readings of the alarm memory information
• Interface conversion towards other field buses or communications networks.
Fig. 4: R485 connection between DSR regulators and PC, through DI1 digital interface

Instruction Manual DSR digital regulator - rev. 05 - pag. 12
PARAMETERS AND OPERATING DATA
1. ModBus Registry List
An EEPROM memory is used to store configuration parameters and other information that must not be lost
when the generator goes off. Parameters can be read/written and machine operational settings entered
through serial connections. Two versions of this regulator are available: DSR and DSR/A; they differ
mainly in the default parameters. Table 3 shows a complete list of the parameters that can be set, which
define all the operational conditions of the regulator.
TABLE 3 : EEPROM SETTING REGISTRIES
    Description of Parameter Range        
       
(1)

0 Firmware revision  15 15 Reserved - Do not write
1 ModBus slave address  1 1 Identification of RS485 network (or broadcast)
2 Software configuration  18 2706
(2)
Reserved - Do not write
3 Serial number, high part   0 0 Reserved - Do not write
4 Serial number, low part   0 0 Reserved - Do not write
5 RMS sensing calibration  16384 16384 Calibration of voltage channels in 3 ph adjustment
6 AVG sensing calibration  16384 16384 Calibration of voltage channels in 1 ph adjustment
7 Measured voltage calibration  16384 16384 Calibration of location L 36 (first “STATUS” box)
8 Current limit time
(3)
 0 0 Duration of limiting in number of periods
(3)
9 Current limit level
(3)
 32767 32767 Excitation voltage limit upon start-up
(3)
10 Word configuration   7965 7965 Set from “Configuration” Menu”, see Tab. 7
11    ! " # $ $   4 5
12    ! " #   3 1
13 Coefficient tieing Ki to Kp  16384 26624 Coefficient to set Ki and Kp separately
14 Vout / Vaux Ratio %  6000 6000 & ' (
15 ' ) *   16384 16384 ) &  ) * $ &  +,-.&  &
(2)

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17 5 6 & ( 7   126 126    5 6 &  & ( 

18 Step limitation reference  20 20 " $ & $  $   8 $   & & &  & $ 
 $ & 
19 Vout Reference  0 0 ) &  ) 6 # &  & 
20 Stability  16384 16384 ) &   # 9&  & 
21 " '   & ±3 '

  16384 16384 ) &  : ; &  & 
22 ! *   &   16384 16384 ) &  5 &  & 
23 ) <"  $   9000 9000 ) <" $ & $ 
24 ) <" $ $   12000 12000 = & ( $ $ 
25     20 20 6 $ >   & * $ &  
& /? & 4+@ * &  # 6 5 .
26 6 $ &   &  %  0 0 ) /±3 4$ & >  $ 
 & <: ; 
27 Shutdown threeshold  6553 6553 Reserved - Do not write
28 A 0*   12287 12287 B& $ $ * 
29 A $ 0*   24575 24575
30 #  & $   63600 63600 = &  ( 5 $ 
31 Reserved  - - Do not write
n=0…6 is equivalent to a multiplication by 2
n
NOTE: Locations are ordered to separate the parameters of individual regulators (S.N:, SW versions and
calibration) from settings foreseen, in order to facilitate programming of regulators with the same settings
but different S.N., SW versions and calibrations. The parameters from 0 to 9 are adjusted at the factory for
each regulator. The parameters from 10 to 30 can therefore be freely copied from one to another.
NOTE (1) starting from rev.10 of the Firmware
NOTE (2) starting from rev.15 of the Firmware, 2578 in previous versions
NOTE (3) starting from rev.15 of the Firmware

Instruction Manual DSR digital regulator - rev. 05 - pag. 13
2. Configuration word (Parameter P[10])
Configuration of the regulator takes place by setting the individual bits of parameter P[10]. Each of them
enables or disables at least one function, on the basis of the fact that its value is respectively 1 or 0.
If the "DSR Terminal" programme is used (see the Chapter on "Use of DSR Terminal monitoring and
programming software"), the setting is facilitated with the Configuration menu, where each box enables or
disables a function and corresponds to the respective bit.
Alternatively, the DSR can be configured by directly setting the value of the P[10] parameter; in this case
the value is calculated before entry, summing the numbers indicated in the column "Value" of Table 4,
corresponding to the functions it is desired to enable.
For example, the default configuration calls for the bits B0, B2, B3, B4 and those from B8 to B12 to be
enabled. The corresponding value is therefore: P[10]=1+4+8+16+256+512+1024+2048+4096=7965.
Bit Value Function   
B0 1 RMS regulation 1
B1 2 Periodical reference variation 0
B2 4 Automatic voltage offset compensation 1
B3 8 Voltage measurement by last 32 samples 1
B4 16 Enable hardware jumper 50/60Hz 1
B5 32 Free for future use 0
B6 64 Not used 0
B7 128 External location reference L[49]
(1)
and activation of saturation in the event of overflow
(2)
0
B8 256 Enable VOLT TRIMMER 1
B9 512 Enable STAB TRIMMER 1
B10 1024 Enable Hz TRIMMER 1
B11 2048 Enable AMP TRIMMER 1
B12 4096 Enable external analogical input 1
B13 8192 Enable external DAC 0
B14 16384 60 Hz setting in the event of disabling of the 50/50 Hz hardware jumper 0
B15 32768 Reserved 0
TABLE 4 : BIT FUNCTION OF THE CONFIGURATION WORD (PARAMETER P[10] )
3. RAM location reference, activation of saturation in analogical remote control
The RAM Voltage CTRL Flag (corresponding to bit 7 of the P[10] configuration word) performs two func-
tions:
1. If the Pext hardware input is enabled (Flat Ext. Input corresponding to bit 12 of the P[10] configuration
word), the RAM Voltage CTRL Flag activates saturation of output voltage when the analogical control
voltage reaches the limit foreseen for input, to which it is applied (see Para. 8 Remote control of
voltage).
If saturation is enabled, in the event of removal of the Vext/Pext connection (due to accidental
opening, for example) the voltage goes to the maximum value set in parameter P[16] (+14% by
default).
2. When hardware input Pext is disabled, the indicated flag defines the value to be used by the software
control of the output voltage. If RAM Voltage CTRL is deactivated (B7=0), the non volatile parameter
P[15] is used (therefore following shut down and restart of the regulator, the last value memorised
remains set): on the start up the location L[49] is initialised with the value of parameter P[15] and is
kept aligned to that value. Editing of location L[49] has no effect in this working condition. If RAM
Voltage CTRL is active (B7=1) the volatile location L[49] is used for software remote control of the
output voltage (when the regulator is energized, the value is stored; if the regulator is shut down, the
value is lost). This function is particularly useful for the applications of alternators in parallel with grid,
when the regulation of the reactive power exchanged is controlled by means of a third party supplied
digital supervisor.
FLAG RAM
Voltage CTRL P[10] Bit B7 FLAG Ext. Input P[10] Bit B12 Output voltage control type


0 1 Analogical without saturation


1 1 Analogical with saturation


0 

0 Digital - Parameter P[15]


1 

0 Digital - Location L[49]
TABLE 5 : REMOTE VOLTAGE CONTROL FLAGS FUNCTION
NOTE (1): if analogical input is disabled, starting from rev.15 of the Firmware
NOTE (2): for analogical input, starting from rev.15 of the Firmware

Instruction Manual DSR digital regulator - rev. 05 - pag. 14
4. Volatile memory addresses
    Add name Range Access Description
32 VOLT Trimmer 0..32767 Read only VOLT Trimmer Position
33 STAB Trimmer 0..32767 Read only STAB Trimmer Position
34 Hz Trimmer 0..32767 Read only Hz Trimmer Position
35 AMP Trimmer 0..32767 Read only AMP Trimmer Position
36 First status word 0..3200 Read only Regulated voltage [tenths of volts]
37 Second status word 0..900 Read only Frequency [tenths of Hz]
38 Third status word 16bit Read only Active alarms
39 Fourth status word 16bit Read only Active configuration
40 Commands 16bit Write Reserved Word Commands – Do not use
41 Pext/Vext Inputs 0..32767 Read only Analogical input or external potentiometer value
42 Setpoint 0..32767 Read only Setpoint value
43 Setpoint 0..32767 Read only ) & &  ( 0
44 Measured Voltage 0..32767 Read only Internal variable
45 Estimated temperture 0..32767 Read only Estimates temperature of exciter windings
… … …
49 $ & ) *  0..32767 Write Used if Vext input is disabled and voltage remote
control by RAM location is enabled (P[10]-Bit B7=1)
53 Kp/2
P[11]
0..32767 Read only Proportional gain not considering factor 2
P[11] (1)
54 Ki/2
P[12]
0..32767 Read only Integral gain not considering factor 2
P[12] (1)
55 AMP protection threshold 0..32767 Read only Intervention threshold of overexcitation protection
(1)
… … 0..32767 …
TABLE 6 : VOLATILE MEMORY ADDRESSES
… … …
Bit Function Value   
B0 Active RMS Regulation 1 1
B1 Bit activating a periodical variation of reference voltage 2 0
B2 Bit activating automatic compensation of the offset in voltage acquisition channels 4 1
B3 Voltage measurement by last 32 samples 8 1
B4 Bit enabling reading of 50/60 Hz jumper hardware 16 1
B5 Free for future use 32 0
B6 Not used 64 0
B7 Voltage remote control by RAM location L[49] or input saturation ( in case of overflow )
(1)
128 0
B8 Bit enabling reading of reference voltage by VOLT Trimmer 256 1
B9 Bit enabling reading of stability parameter by STAB Trimmer 512 1
B10 Bit enabling reading of underspeed protection threshold by Hz Trimmer 1024 1
B11 Bit enabling reading of excitation current threshold by AMP Trimmer 2048 1
B12 Bit enabling reading of external voltage input 4096 1
B13 Bit enabling DAC 8192 0
B14 60Hz active setting (jumper 60Hz closed and/or 60Hz active setting on configuration menu) 16384 0/1
B15 Reserved 32768 0
TABLE 8 : BIT FUNCTION OF THE FOURTH STATUS WORD L[39] (ACTIVE CONFIGURATION) 
5. Fourth Status Word (Location L[39])
Location L[39] indicates (almost in real time) the active configuration at any given time.
The values of the fourth word of status (location L[39]) are shown in table 7, on the basis of the most com-
mon types of sensing and nominal frequency.
TABLE 7 : STANDARD VALUES OF THE FOURTH STATUS WORD (LOCATION L[39])
Rated frequency:
50Hz 60Hz
RMS 7965 24349
AVG + no offset compensation + 64 samples 7952 24336
Regulation
NOTE (1) : starting from rev.15 of the Firmware.

Instruction Manual DSR digital regulator - rev. 05 - pag. 15
IMPOSTAZIONE DEI PARAMETRI VOLT, STAB, AMP Hz.
1. Voltage
1.1 Setting voltage
Measurement of the rms or average value is decided from the Configuration Menu.
The voltage setting may take place through the trimmer or software; the sensing input range on CN1-6 and
CN1-7 is 70÷140 Vac; the sensing input range on CN1-4 and CN1-5 is 140÷280 Vac.
There are two ways to set the value from the minimum to the maximum:
1. Through the VOLT trimmer, which must be enabled from the Configuration Menu.
2. Through parameter 19 (the Volt trimmer must be disabled from the Configuration Menu: A value of 0
corresponds to minimum voltage, 16384 corresponds to the intermediate value (respectively, 105V
and 210V), while 32767 corresponds to the maximum voltage.
For standard voltage values refer to table 9.
Voltage CN1 4&5 Voltage CN1 6&7 Volt Trimmer (Location 32) Parameter 19
 0 , ,
0  C C
  ,, ,,
C , - -
  C C
   
,  , ,
  -,- -,-
 C  
TABLE 9 : STANDARD VOLTAGE VALUES
It is possible to vary the voltage through the Vext input as well (connector CN1-10 and CN1-11), providing
it has been enabled from the Configuration Menu, through a 10Kohm potentiometer with a programmable
variation range of up to ±100% (parameter 16; the default setting is ±14%, even if it is convenient do not
exceed more than ±10%), or through a continuous voltage, which will be effective it is in the range
between 0V and +2,5V, or even through parameter P [15] or location L[49] (if the Vext input is disabled).
For additional details see the paragraph "Remote control of voltage".
1.2 Soft Start (starting from rev.15 of the Firmware)
In the event of fast start up of the prime mover or sudden regulator switching on, with generator running at
nominal speed, to guarantee the nominal voltage the excitation current should quickly change and therefo-
re it could happen an engine braking effect or temporary generator overvoltage.
These effects can be minimised by setting parameter P[8] and P[9] appropriately. In the phase of start up,
they determine a limit of the excitation current.
Parameter P[8] sets the duration of the excitation current limitation, namely the value of the
parameter corresponds to the number of periods in which the limitation is active. The default
value is P[8]=0 which corresponds to deactivation of the soft start. Considering that in most cases
the alternator is already at nominal speed, an estimate in temporal terms may be obtained with
the formula :
The parameter P[9] sets the excitation current limit: the value P[9]=0 corresponds to zero excitation
current, while the maximum value P[9]=32767 corresponds to no limits on the current limitation. The
default value is P[9]=32767. When the interval of action of the soft start has been exceeded, the output
voltage moves to the value set. The rapidity of the change is set by parameter P[18] (see paragraph on
"Slow voltage variations”)
Where f
n
= nominal frequency in Hz or ω
n
= nominal speed in R.P.M
nn
P
f
Pt
ω
30
]8[
1
]8[
lim
⋅=⋅=
By way of example, for high power alternators of the ECO46 series, the following settings may be
experimented: P[8]=64 and P[9]=16384; for low power alternators of the ECO/ECP3 series, the effects of a
reduction of both the duration and limitation of the current may be experimented, such as P[8]=16 and P[9]
=4096.
The optimal values of parameters P[8] and P[9] depend a great deal on the type of alternator
and final application and it must be found through experimentation. An inappropriate setting of
parameters P[8] and P[9] could cause failure of the alternator to excite itself.

Instruction Manual DSR digital regulator - rev. 05 - pag. 16
16384
21065
P19
210V
230V
P18 = 20
P18 = 1
t
t
P18 = 100
Vo
1.2 Slow voltage variations
In the event of a reference rapid variation, due to a regulator sudden feeding, or remote voltage setting
(through Vext analogic input or through serial) a procedure of "slow" variation has been foreseen: in re-
sponse to a step variation, parameter P[18] determines the rapidity with which the transition is made.
(see fig. 5)
A value of 1 involves the slowest possible variation; a value exceeding 100 involves an almost immediate
variation. The value 0 disables any variation.
2. Stability
2.1 Stability regulation
The voltage regulator is of the proportional-integral type, the diagram is shown in fig. 6.
K
P
K
I
s

++
+
-
Ref.
Feedback
Error PI
out
fig. 6: regulator diagram
The values of the proportional and integral gain (K
P
and K
I
respectively) depend on the position of the
STAB trimmer if enabled, or the value of parameter P[20] if the trimmer is disabled. The value of the pro-
portional gain K
P
also depends on the value of the P[11] parameter. The value of the integral gain K
I
de-
pends on the values of parameters P[12] and P[13] and, only for the standard DSR (grey box) with the
STAB trimmer enabled, even on the 50/60Hz
(1)
setting. In the other DSR versions, for example DSR/A
(blue box), the integral gain K
I
does not differ no matter how the 50/60Hz
(4)
setting is set.
The numeric elaborations carried out by the DSR for obtaining the proportional and integral gain values
are given in the block diagrams in figures 6a
(2)
, 6b
(2)
and 6c .
fig. 6a: drawing of the numeric elaboration of the proportional and integral
gain by a DSR (standard) with the STAB trimmer enabled
Trimmer
STAB
L[33]
Fcig
50
() <<<&  Fcig
60
()
L[53]
2
P[11]
K
P
2
P[12]
K
I
P[13]
L[54]
Fc
STAB
()
fig. 5

Instruction Manual DSR digital regulator - rev. 05 - pag. 17
If the STAB trimmer is enabled (STAB Flag Trimmer present) its angular position, available at location
L[33], is transformed by the Fc
STAB(2)
function into the numeric value available at location L[53]
(3)
(figs. 6a
and 6b). If the STAB trimmer is disabled, the value of location L[53]
(3)
directly becomes the value set using
the P[20] parameter (fig. 6c).
The proportional gain K
P
is obtained by multiplying the value of location L[53]
(3)
by a coefficient that de-
pends on the value given in parameter P[11]
(4)
.
NOTE (1) Starting from Rev. 15 of the firmware
NOTE (2) The Fc
STAB
, Fcig
50
and Fcig
60
functions are not implemented in the DSRs with firmware up to version 14, and in the
block diagram they are considered as identities, i.e. L[53]
(3)
=Fc
STAB
(L[33])=L[33] e Fcig
60
(L[53] ) = Fcig
50
(L[53])=L[53]
(3)
.
With these regulators the STAB trimmer needs to be rotated by less than two notches counted clockwise.
NOTE (3) Location available to the user from firmware Rev. 15.
NOTE (4) Structure valid also for DSRs with firmware up to version 14 but without location L[53] and L[54] availability
Trimmer
STAB
L[33] L[53]
2
P[11]
K
P
2
P[12]
K
I
P[13]
L[54]
Fc
STAB
()
fig. 6b: drawing of the numeric elaboration of the proportional and integral
gain by a DSR/A with the STAB trimmer enabled
The integral gain, available at location L[54]
(3)
minus the multiplication by a coefficient, depends on the va-
lue of the proportional gain at location L[53]
(3)
; in the standard DSR (grey box) with the STAB trimmer
enabled (STAB Flag Trimmer present) the value of location L[53]
(3)
at 50Hz is transformed by the function
Fcig
50(2)
and by the multiplication of the value of parameter P[13], in the numeric value available at location
L[54]
(3)
; at 60Hz the transformation function is Fcig
60(2)
, different from that at 50Hz, (fig. 6a); in the other
versions of the DSR (fig. 6b), for example DSR/A (blue box), or if the STAB trimmer is disabled
(4)
(fig. 6c),
not only is there a difference between the integral value at 50Hz and at 60Hz, but even the value of loca-
tion L[54]
(3)
is obtained by simply multiplying the proportional gain at location L[53]
(3)
by the value of para-
meter P[13].
L[53]
2
P[11]
K
P
2
P[12]
K
I
P[13]
L[54]
P[20]
fig. 6c: drawing of the numeric elaborations of proportional and integral gain by all
DSRs with STAB trimmer disabled
In both cases, the effective integral gain K
I
is obtained by multiplying the value of location L[54]
(3)
by a co-
efficient that depends on the value given in parameter P[12]
(4)
.
The mentioned coefficients can take on values of 1, 2, 4, 8, 16, 32 or 64 according to the values written in
parameters P[11] (for proportional gain) and P[12] (for integral gain); these values represent the value as-
signed to base 2 (fixed) to obtain the required coefficient (e.g. parameter P[11] = 4 => multiplication coeffi-
cient of the proportional gain = 2
4
= 16, P[12] = 3 => multiplication coefficient of the integral gain = 2
3
= 8).
The following tables, for each 50Hz and 60Hz machine, show the setting of the STAB trimmer that gives
the best answer speed to the transient with the gen-set in single operation. In the case of different appli-
cations (for example alternators in parallel or in parallel with grid, motors with less than 4 cylinders, etc.) it
may be necessary to modify the settings of the STAB trimmer. If the voltage cannot be stably adjusted for
permanent operation and/or in the transisient by the STAB trimmer settings, it may be necessary to vary
one or more stability adjustment parameters: P[11], P[12] and P[13] the description of which is given in
table 3.

Instruction Manual DSR digital regulator - rev. 05 - pag. 18
Generator 115/200/230/400V 50Hz 138/240/277/480V 60Hz
Type
   
S [KVA] STAB L[33] L[53] S [KVA] STAB L[33] L[53]
ECP3-1SN/2 28512480 4753 9,6 48576 2245
ECP3-2SN/2 210 512480 4753 12 4½ 10559 3403
ECP3-3SN/2 212,5 512480 4753 15 4½ 10559 3403
ECP3-1LN/2 216 5½ 14400 6328 19,2 512480 4753
ECP3-2LN/2 219 5½ 14400 6328 22,8 512480 4753
ECO28-1LN/2 222 6½ 18368 10296 26,4 n.a. n.a. n.a.
ECO28-2LN/2 227 5½ 14400 6328 32,4 5½ 14400 6328
ECO28-3LN/2 231,5 512480 4753 37,8 n.a. n.a. n.a.
ECO28-VL/2 240 7½ 22208 15051 48 616384 8192
ECO31-2SN/2 244 n.a. n.a. n.a. 52,8 n.a. n.a. n.a.
ECO31-3SN/2 255 n.a. n.a. n.a. 66 n.a. n.a. n.a.
ECO31-1LN/2 266 n.a. n.a. n.a. 79,2 512480 4753
ECO31-2LN/2 282 n.a. n.a. n.a. 98,4 n.a. n.a. n.a.
ECO3-1SN/4 46,5 616384 8192 7,8 616384 8192
ECO3-2SN/4 485½ 14400 6328 9,6 4½ 10559 3403
ECO3-1LN/4 411 512480 4753 13,2 4½ 10559 3403
ECO3-2LN/4 413,5 616384 8192 16,2 5½ 14400 6328
ECO3-3LN/4 415 6½
(2)
18368
(2)
10296
(2)
18 5½ 14400 6328
ECO28-1VS/4 47,8 512480 4753 9,3 48576 2244
ECO28-2VS/4 411 48576 2244 13,2 48576 2244
ECO28-OS/4 413,5 5½ 14400 6328 16,2 512480 4753
ECO28-SN/4 417 616384 8192 20,4 5½ 14400 6328
ECO28-1LN/4 420 5½ 14400 6328 24 512480 4753
ECO28-2LN/4 425 720288 12561 30 512480 4753
ECO28-VL/4 430 7
(3)
20288
(3)
12561
(3)
36 6
(3)
16384
(3)
8192
(3)
ECO32-2S/4 435 5½ 14400 6328 42 4½ 10559 3403
ECO32-3S/4 440 616384 8192 48 616384 8192
ECO32-1L/4 450 7½ 22208 15051 60 48576 2244
ECO32-2L/4 460 824191 17860 72 5½ 14400 6328
ECO32-3L/4 470 8½ 26176 20908 84 5½ 14400 6328
ECP34-1S/4 485 7½ 22208 15051 102 720288 12561
ECP34-2S/4 4105 6½ 18368 10296 126 6½ 18368 10296
ECP34-1L/4 4130 8½ 26176 20908 156 6½ 18368 10296
ECP34-2L/4 4150 8½ 26176 20908 180 824191 17860
ECO38-1SN/4 4180 928096 24090 216 6½ 18368 10296
ECO38-2SN/4 4200 928096 24090 240 824191 17860
ECO38-3SN/4 4225 8½ 26176 20908 270 7½ 22208 15051
ECO38-1LN/4 4250 8½ 26176 20908 300 824191 17860
ECO38-2LN/4 4300 824191 17860 360 max 32704 32640
ECO38-3LN/4 4350 max 32704 32640 420 9½ 30077 27610
TABLE 10 ECO/ECP SERIES: ADVISED STAB TRIMMER SETTING ON DSR
(1)
Fw Rel. 15
NOTE 1) DSR: P[11] = 4, P[12] = 3, P[13] = 16384, with STAB trimmer enabled
NOTE 2) For standard application; for special application: STAB=4 L[33]=8576 L[53]=2244;
NOTE 3) For standard application; YY 230V/60Hz and singlephase 230V/50Hz: STAB=6 L[33]=16384 L[53]=8192;
NOTE 4) Dedicated winding
NOTE 5) DSR/A: P[11] = 5, P[12] = 1, P[13] = 26624, with Fcig
60
(L[53] ) = Fcig
50
(L[53]) = L[53]

Instruction Manual DSR digital regulator - rev. 05 - pag. 19
NPE32 1-PHASE
(4)
230V / 50Hz 240V / 60Hz
Type
   
S [KVA] STAB L[33] L[53] S [KVA] STAB L[33] L[53]
NPE 32-A/4 46,4 6 ½ 18368 10296 8,4 n.a. n.a. n.a.
NPE 32-B/4 48,7 5 ½ 14400 6328 10,5 5 ½ 14400 6328
NPE 32-C/4 410,8 616384 8192 13 616384 8192
NPE 32-D/4 413,8 720288 12561 17 5 ½ 14400 6328
NPE 32-E/4 418,5 n.a. n.a. n.a. 22 616384 8192
NPE 32-F/4 422,5 616384 8192 26,5 616384 8192
TABLE 11 NPE32/4: ADVISED STAB TRIMMER SETTING ON DSR
(1)
Fw Rel. 15
NPE32 3-PHASE 115/200/230/400V 50Hz 138/240/277/480V 60Hz
Type
   
S [KVA] STAB L[33] L[53] S [KVA] STAB L[33] L[53]
NPE 32-A/4 47,5 4 ½ 10559 3402 9512480 4753
NPE 32-B/4 411,5 5 ½ 14400 6328 14 512480 4753
NPE 32-C/4 413 n.a. n.a. n.a. 16 n.a. n.a. n.a.
NPE 32-D/4 417 5 ½ 14400 6328 21 512480 4753
NPE 32-E/4 425 616384 8192 31 512480 4753
NPE 32-F/4 427,5 5 ½ 14400 6328 34 512480 4753
Generator Nominal Frequency = 50Hz Nominal Frequency = 60Hz
Type
   
S [KVA] STAB L[33] L[53] S [KVA] STAB L[33] L[53]
ECO40-1S/4 4400 928096 24090 480 720288 12561
ECO40-2S/4 4450 8½ 26176 20910 540 824191 17860
ECO40-3S/4 4500 928096 24090 600 8½ 26176 20908
ECO40-1L/4 4550 928096 24090 660 8½ 26176 20908
ECO40-1.5L/4 4620 928096 24090 744 n.a. n.a. n.a.
ECO40-2L/4 4680 9½ 30077 27610 816 720288 12561
ECO40-VL/4 4720 928096 24090 864 7½ 22208 15051
ECO43-1SN/4 4800 928096 24090 960 7½ 22208 15051
ECO43-2SN/4 4930 928096 24090 1116 824191 17860
ECO43-1LN/4 41100 928096 24090 1320 8½ 26176 20908
ECO43-2LN/4 41300 9½ 30077 27610 1560 824191 17860
ECO43-VL/4 41300 9½ 30077 27610 1560 824191 17860
ECO46-1S/4 41500 824191 17860 1800 6½ 18368 10296
ECO46-1,5S/4 41800 928096 24090 2160 8½ 26176 20908
ECO46-2S/4 41800 8½ 26176 20908 2160 824191 17860
ECO46-1L/4 42100 max 32704 32640 2520 928096 24090
ECO46-1,5L/4 42500 928096 24090 3000 928096 24090
ECO46-2L/4 42500 9½ 30077 27610 3000 928096 24090
TABLE 12 ECO40-43-46: ADVISED STAB TRIMMER SETTING ON DSR
(5)
Fw Rel. 15
NOTE 1) DSR: P[11] = 4, P[12] = 3, P[13] = 16384, with STAB trimmer enabled
NOTE 2) For standard application; for special application: STAB=4 L[33]=8576 L[53]=2244;
NOTE 3) For standard application; YY 230V/60Hz and singlephase 230V/50Hz: STAB=6 L[33]=16384 L[53]=8192;
NOTE 4) Dedicated winding
NOTE 5) DSR/A: P[11] = 5, P[12] = 1, P[13] = 26624, with Fcig
60
(L[53] ) = Fcig
50
(L[53]) = L[53]

Instruction Manual DSR digital regulator - rev. 05 - pag. 20
0
5000
10000
15000
20000
25000
30000
0 5 10 15 20 25 time [sec]
Loction 45
L45(alt1,I=In)
L45(alt2,I=In)
L45(alt2,I>In)
T45(alt1,I=In)
T45(alt2,I=In)
T45(alt2,I>In)
L[55]=12970
L[55]=21617
3. Excitation Overcurrent
3.1 Description
The DSR regulator is equipped with an excitation (main rotor) winding temperature estimator. An estimate
of the temperature is memorised in real time (and can be read) at location 45. The progress of the tempe-
rature is of the exponential type (see figure 7).
Through parameter 22 or the AMP trimmer, it is possible to define a limit (which involves intervention of
alarm 5) to the excitation voltage and therefore to the temperature.
The function of this alarm is not only to signal an excessive temperature, but it also has an active function
in reducing the cause. In fact, an adjustment ring takes control of the voltage generated when the thre-
shold set is exceeded: This reduces the voltage to the point of reducing the excitation current by a value
compatible with the ability of thermal dissipation of the machine. The stability of the adjustment in the
event of over-excitation alarm can be set with parameters 28 and 29. The default values are suitable for
the great majority of machines.
WARNING !
If the magnetic gain of the alternator is high, unstable situations can be created upon intervention of the
protection, therefore it is necessary to adjust parameters 28 and 29 (in general it is sufficient to lower para-
meter 28). As you can see in figure 7, when the estimated temperature (represented by the continuous
line) reaches the threshold value set in parameter 22, the reduction of excitation current (and consequent
drop in voltage generated) brings about the stabilisation of the temperature near a limit value.
Curve Description
L45 (alt1, I=In) : value read at location 45 with a certain alternator
(1)
L45 (alt2, I=In) : value read at location 45 with a second alternator of a different type
(1)
L45 (alt2, I>In) : value read at location 45 with the second alternator during overloading
(2)
T45 (alt1, I=In) : value that would be read at location 45 with the first alternator, without protection
(1)
T45 (alt2, I=In) : value that would be read at location 45 with the second alternator, without protection
(1)
T45 (alt2, I>In) : value that would be read at location 45 with the second alternator during overloading,
without protection
(2)
L[55]=12970 Represents the value of the current limit set using the AMP trimmer or the P[22] parameter
for the first alternator
(3)
L[55]=21617 Represents the value of the current limit set using the AMP trimmer or the P[22] parameter
for the second alternator
(3)
3.2 Calibration with a supervising unit
Use the following procedure in order to calibrate the overload protection:
1) Lower the underspeed protection threshold, rotating the Hz trimmer counter clockwise (if it has been
enabled from the Configuration Menu) or by entering 0 at location 21.
2) Rotate the AMP trimmer completely in the clockwise direction (if it has been enabled from the
Configuration Menu) or enter 32767 at location 22.
3) Apply the nominal load to the alternator.
4) Decrease the speed by 10%
5) Read the value shown at location 45, two minutes after reducing the speed.
6) If the AMP trimmer is enabled, rotate it counter clockwise until the value shown at location 55
(4)
becomes the same as the value read at point 5 (location 45); otherwise (trimmer not enabled) enter the
value read at point 5 (location 45) at location 22.
fig. 7
(1) Nominal load and 90% of nominal frequency
(2) with load greater than the nominal one
(3) starting from rev.15 of the Firmware
(4) starting from rev.15 of the Firmware, L[35] for
the previous versions