Hyundai HPC-250HT User manual

HPC-250HT
Photovoltaic Inverter
User Manual

USER MANUAL of HPC-250HT
PE07019-022-B Page 2 of 69
Table of Contents
1NOTES ON THIS MANUAL...................................................................................................................... 4
1.1 TARGET GROUP AND APPLICABILITY ..................................................................................................... 4
2SAFETY INSTRUCTIONS......................................................................................................................... 5
3DESCRIPTION OF THE HPC-250HT...................................................................................................... 6
3.1 IDENTIFYING THE HPC-250HT .............................................................................................................. 6
3.2 THE HPC-250HT’S CONTROL ELEMENTS.............................................................................................. 6
3.2.1 AC Side Rotary Handle Circuit Breaker ........................................................................................... 7
3.2.2 Emergency-Off Button (-S2).............................................................................................................. 8
3.2.3 Start / Stop Key Operated Spring-Return Switch (-S1) ..................................................................... 9
3.2.4 HPC-250HT User Interface ............................................................................................................ 10
3.2.5 Light Indicators (-H1, -H2)............................................................................................................. 11
3.3 OPERATING MODES.............................................................................................................................. 11
3.3.1 Operating Modes of the HPC-250HT ............................................................................................. 12
3.3.1.1 Automatic Startup................................................................................................................................... 12
3.3.1.2 Waiting after Grid Failure...................................................................................................................... 13
3.3.1.3 Testing of String Voltage ....................................................................................................................... 14
3.3.1.4 Grid Voltage and Frequency Test........................................................................................................... 15
3.3.1.5 Connecting to Solar Arrays .................................................................................................................... 16
3.3.1.6 Connecting to Grid, Test of String Voltage............................................................................................ 17
3.3.1.7 Feeding to the Grid (4)........................................................................................................................... 18
3.3.1.8 Shut Down (5)........................................................................................................................................ 20
3.3.1.9 Disconnecting from Grid........................................................................................................................ 21
3.3.1.10 Offline.................................................................................................................................................... 22
4HPC-250HT CONTROL OPERATION .................................................................................................. 23
4.1 HPC-250HT CONTROL MENU ............................................................................................................. 23
4.2 OVERVIEW OF THE MENU..................................................................................................................... 25
4.2.1 Start (Brief Description).................................................................................................................. 25
4.2.2 Online Info (Brief Description)....................................................................................................... 26
4.2.3 Fault Handling (Brief Description)................................................................................................. 27
4.2.4 Log (Brief Description)................................................................................................................... 28
4.2.5 System (Brief Description) .............................................................................................................. 29
4.2.6 Email (Brief Description)................................................................................................................ 30
4.2.7 Operator (Brief Description) .......................................................................................................... 31
4.2.8 Setting 1 (Brief Description) ........................................................................................................... 32
4.2.9 Setting 2 (Brief Description) ........................................................................................................... 33
4.2.10 Start (Detailed Description) ....................................................................................................... 34
4.2.11 Online Info (Detailed Description)............................................................................................. 35
4.2.12 Fault Handling (Detailed Description)....................................................................................... 37
4.2.13 Log (Detailed Description)......................................................................................................... 38
4.2.14 System (Detailed Description).................................................................................................... 39
4.2.15 Email (Detailed Description)...................................................................................................... 41
4.2.16 Operator (Detailed Description) ................................................................................................ 42
4.2.17 Setting 1 (Detailed Description)................................................................................................. 44
4.2.18 Setting 2 (Detailed Description)................................................................................................. 46
4.3 OPERATOR LOGIN/LOGOUT.................................................................................................................. 47
4.3.1 Log ON Procedure.......................................................................................................................... 48
4.3.2 Add Operator Password.................................................................................................................. 48
4.3.3 Log OFF procedure ........................................................................................................................ 50
4.4 CHANGING DATE AND TIME................................................................................................................. 51
5PARAMETERS.......................................................................................................................................... 52
5.1 DESCRIPTION OF THE PARAMETER FUNCTIONS .................................................................................... 52
5.2 DEFAULT PARAMETER SETTINGS ......................................................................................................... 54
5.3 ENTERING PARAMETERS AND SETTINGS .............................................................................................. 56

USER MANUAL of HPC-250HT
PE07019-022-B Page 3 of 69
6COMMUNICATION................................................................................................................................. 57
6.1 ENTERING OR CHANGING EMAIL ADDRESSES ...................................................................................... 57
6.2 SELECTING THE REPORT TYPES TO SEND ............................................................................................. 59
6.3 SENDING A TEST EMAIL ....................................................................................................................... 60
7FAULTS...................................................................................................................................................... 63
7.1 FAULT DIAGNOSTICS............................................................................................................................ 63
7.1.1 Types of Faults................................................................................................................................ 63
7.1.1.1 Emergencies ........................................................................................................................................... 63
7.1.1.2 Alarms.................................................................................................................................................... 64
7.1.1.3 Trips ....................................................................................................................................................... 64
7.1.1.4 Failure handling...................................................................................................................................... 67
7.2 CONFIRMING FAULTS ON THE HPC-250HT USER INTERFACE.............................................................. 68
8CONTACT.................................................................................................................................................. 69

USER MANUAL of HPC-250HT
PE07019-022-B Page 4 of 69
1 Notes on this Manual
1.1 Target Group and Applicability
The purpose of this manual is to be an aid for HPC-250HT installers and operators in
installing, operating, maintenance and troubleshooting of the HPC-250HT Photovoltaic
Inverter. It serves as a rule regarding the operation of the HPC-250HT and User Interface,
and applies for UI software version 1.0.
This manual was written with the greatest possible care. However, discrepancies cannot be
excluded.

USER MANUAL of HPC-250HT
PE07019-022-B Page 5 of 69
2 Safety Instructions
Risk of life-threatening injuries!
- Special care is required if working with components of the HPC-250HT which are
connected to the utility grid or solar power plant!
- Do not touch the live – voltage carrying or current carrying - components of the HPC-
250HT, the utility grid or the solar plant!
- Follow all the regarding safety instruction, directives and regulations which go for
working on a low-voltage utility grid!
- All actions during installation, operation, troubleshooting and maintenance or any
other cause have to be carried out by qualified and trained technician!
- All actions described in this manual that are performed on the HPC-250HT have to be
carried out as described in the following sections of this user manual.
- Safety instructions found in the HPC-250HT Installation Guide must also be taken
into account!
- Damage to the HPC-250HT may engender lethal danger due to fire or electric shock!
- Be sure to only use HPC-250HT Photovoltaic Inverter if it is secure to do so!
- Be sure to only use HPC-250HT Photovoltaic Inverter if damage is obviously absent!
- Visually examine the HPC-250HT at regular intervals!
- Be sure that all of the external safety equipments are readily accessible at any time
and that their reliable performance is tested on a regular basis!
- Before working with electronic components of the HPC-250HT Photovoltaic Inverter
always remember to discharge any electrostatic charge by touching the grounded
cabinet housing!
- Before working with electronic components of the HPC-250HT Photovoltaic Inverter
do not forget to review all ESD security regulations!
This document alongside the installation guide and wiring diagrams of the HPC-250HT
Photovoltaic Inverter must be available to operators, maintenance and troubleshooting staff
every time.

USER MANUAL of HPC-250HT
PE07019-022-B Page 6 of 69
3 Description of the HPC-250HT
The HPC-250HT is a photovoltaic inverter cabinet for converting solar energy generated by
photovoltaic power modules to three phase, sinusoidal, low level voltages and currents,
ready to be fed back to the utility grid.
3.1 Identifying the HPC-250HT
3.2 The HPC-250HT’s Control Elements
By analyzing the below depiction the user will be able to identify the location of the HPC-
250HT’s control elements!
ID
Description
A
AC Side, Rotary Handle Circuit Breaker (-Q2)
B
User Interface
C,D
Trip (Red) and Alarm (Yellow) Light Indicators (-H1, -H2)
E
Start / Stop Key Operated Spring Return Switch (-S1)
F
Emergency Button (-S2)

USER MANUAL of HPC-250HT
PE07019-022-B Page 7 of 69
3.2.1 AC Side Rotary Handle Circuit Breaker
By means of the rotary handle operated circuit breaker located on the door of the AC cabinet
the HPC-250HT can be manually disconnected from, or connected to the utility grid.
The internal components of the HPC-250HT are exposed to substantial stresses if the AC
side rotary handle circuit breaker is operated under load. Irregular use of the Rotary handle
operating mechanism may cause serious damage to the HPC-250HT.
Only use the Rotary handle operating mechanism if the HPC-250HT has been set to “Offline”
mode using the Start / Stop key operated switch.
The HPC-250HT connects to the utility grid by means of an AC Circuit Breaker. If manually
turned to the “Off” position the circuit breaker isolates the AC contactor (-K1), AC EMC filter
(-A12), transformer (-T1), LC filter capacitor (C1…18) and inductor (-T2) and the 3ph inverter
(-A1) from the utility grid and protects these devices from AC side overcurrent. The AC
Circuit Breaker is equipped with an external lockable rotary handle mounted on the -E2
cabinet door.
The AC side rotary handle circuit breaker can be identified as the device “–Q2” on the picture
below.

USER MANUAL of HPC-250HT
PE07019-022-B Page 8 of 69
3.2.2 Emergency-Off Button (-S2)
By actuating the Emergency-Off Button the HPC-250HT can be immediately disconnected
from both, the utility grid and the solar arrays during any operation condition.
In the DC Cabinet (-E1) the disconnection takes place in the DC Circuit Breaker (-Q1), while
in the AC Cabinet (-E2) the disconnection takes places in the AC Contactor (-K1).
The actual state of the AC Circuit Breaker (-Q2) is not modified by the emergency shut-down
process.
The DC EMC Filter (-A11) and the DC Input Fuses (-F1…16) are not isolated from the DC
network of solar panels and are exposed to the actual voltage level determined by this
network of solar panels.
Excluding the MCU (-A23), cabinet thermostats (-B5, -B6), transformer thermostat (-B1),
inductor thermostats (-B2, -B3) and RS485 Repeater (-A25) power supply, all auxiliary power
supply is turned off by the operation of the Emergency button.
Always bear in mind that not all of the internal components of the HPC-250HT cabinet are
isolated from their power supply, the AC utility grid or the DC network of solar panels after
exerting the Emergency-Off Button (-S2).
When the Emergency-Off Button was pressed, it locks in the pressed position and can only
be released by turning the Emergency button itself according to tha indication arrows.
The internal components of the HPC-250HT are exposed to substantial stresses if the
Emergency Button is used under load. Only use the Emergency Button in case of an
emergency.

USER MANUAL of HPC-250HT
PE07019-022-B Page 9 of 69
3.2.3 Start / Stop Key Operated Spring-Return Switch (-S1)
The key operated spring-return switch (–S1) can be in one of three possible positions START,
STOP and CENTER. START and STOP are momentary positions and the switch
automatically returns to the CENTER position after leaving hold of its operating key.
The HPC-250HT can be set to “Offline” or “Connecting to Solar Arrays” mode, the “Automatic
Startup” sequence can be aborted or skipped and the User Interface backlight illumination
can be turned ON with the Start / Stop Key Operated Spring-Return Switch (-S1).
Instantaneous operation of the Start / Stop Key Operated Spring Return Switch (-S1) in
either direction enables the backlight illumination of the HPC-250HT User Interface. The
backlight illumination of the HPC-250HT User Interface will stay enabled for 60 minutes
counting from the last actuation of the Start / Stop Key Operated Switch in either direction.
In case the system is in “Offline” state, when the switch is turned to the Start position for at
least three seconds the system state of the HPC-250HT changes from “Offline” to
“Conencting to Solar Arrays”.
In case the system is not in “Trip”, “Emergency” or “Waiting after Grid Failure” state, when
the switch is turned to the stop position for at least three seconds the system initializes a shut
down sequence and the system state changes according to, and the steps of this shut-down
sequence depend on the actual state of the system at the moment of the stop request.
Each time the auxiliary power supply was connected to the MCU of the HPC-250HT the
system waits for additional 5 minutes before initiating an automatic start up sequence. This
waiting time can be interrupted by turning the Start/Stop Key operated Switch in Stop
direction for at least three seconds, or skipped by turning the Start/Stop Key Operated Switch
in Start direction for at least 3 second three. If the automatic startup process is skipped, the
operation state is redirected to “Waiting after Grid Failure” state.
Each time the utility grid voltage is disconnected from the HPC-250HT or the power supply is
disconnected from the MCU of the HPC-250HT, the system waits for additional five minutes
counting from the reconnection of the MCU power supply or counting from the moment in
which the stable condition of the utility network has been met, respectively, before the HPC-
250HT is allowed to connect to the utility grid again. Note, that the utility grid stability waiting
time can be in coincidence with the Automatic Start Up waiting time, but can not be
shortened or interrupted.
The conditions, in which the utility network can be considered stable can be defined on the
“Setting 2” tab page of the User Interface and are identified as “Nominal Grid Voltage”,
“Nominal Grid Frequency”, “Minimum Grid Voltage”, “Maximum Grid Voltage”, “Grid
Frequency Limit Fmax-Fnom” and “Grid Frequency Limit Fnom-Fmin”.

USER MANUAL of HPC-250HT
PE07019-022-B Page 10 of 69
3.2.4 HPC-250HT User Interface
The HPC-250HT operation can be observed and the system settings may be modified by
means of the HPC-250HT User Interface. Control, monitoring, reporting and administrative
functions can be exercised, observed and altered using the UI residing at the front of the AC
side cabinet (-E2).
Conveniently situated actions contain:
- Monitoring of System Operation
- Supervising Inverter Operation
- Displaying Online Measurement Data
- Adjustment of Parameters
- Displaying and Acknowledgement of Fault events
- Modification and Test of Communication Parameters
- Observing operation of String Boxes connected
- Supervising and modifying String Box settings
For turning on/off backlight illumination of the HPC-250HT User Interface see chapter 3.2.3!

USER MANUAL of HPC-250HT
PE07019-022-B Page 11 of 69
3.2.5 Light Indicators (-H1, -H2)
In case of a fault during operation of the HPC-250HT, the type of the occurred fault is being
indicated via a red and a yellow light on the front of the AC side cabinet (-E2) of the HPC-
250HT cubicle.
- Yellow
An ALARM event did occur during operation of the HPC-250HT.
The system does not switch itself off.
- Red
A TRIP or EMERGENCY event did occur during operation of the HPC-250HT.
3.3 Operating Modes
OFFLINE
AUTOMATIC
STARTUP
WAITING AFTER
GRID FAILURE
CONNECTING
TO SOLAR
ARRAYS
WAITING AFTER
LOW POWER
STOP
WAITING AFTER
GRID FAILURE
TESTING OF
STRING
VOLTAGE
GRID VOLTAGE
AND
FREQUENCY
TEST
CONNECTING
TO GRID, TEST
OF STRING
VOLTAGE
FEEDING TO
THE GRID
SHUT DOWN
SHUT DOWN
DISCONNECTING
FROM GRID

USER MANUAL of HPC-250HT
PE07019-022-B Page 12 of 69
3.3.1 Operating Modes of the HPC-250HT
During operation, the HPC-250HT shifts trough various states as consequence of various
conditions.
As a safety feature, each time the auxiliary power supply was connected to the HPC-250HT
the system waits for additional five minutes before initiating an automatic start up sequence.
This waiting time can be interrupted by turning the Start/Stop Key operated Switch in Stop
direction for at least three seconds, or skipped by turning the Start/Stop Key Operated Switch
in Start direction for at least three seconds. If the automatic startup process is skipped the
operation state is redirected to “Waiting after Grid Failure” state.
3.3.1.1 Automatic Startup
The system initiates an automatic startup only 5 minutes after connecting the auxiliary power
supply to the MCU of the HPC-250HT. The system is not detecting trip utility network –
related trip events, but emergency and warning events are redirected to the MCU.
The remaining time of the initial 5 minutes is displayed in the Status bar on the User interface.
After 5 minutes the system is leaving this state automatically and steps into “Conencting to
Solar Arrays” state..
The “Automatic Startup” state can be skipped by holding the Start / Stop Key operated
Spring Return Switch in either “Start” or “Stop” position for more than three seconds.
The system can get into this state
- By connecting auxiliary power supply to the HPC-250HT
The system can leave this state
- By holding the Start / Stop Key Operated Spring-Return Switch (-S1) in “Start” or
“Stop” condition for more than three seconds the system switches to “Waiting after
Grid Failure” state
- After 5 minutes counting from entering “Automatic Startup State”, the system is
leaving „Automatic Startup” state automatically and steps into “Connecting to Solar
Arrays” state.

USER MANUAL of HPC-250HT
PE07019-022-B Page 13 of 69
3.3.1.2 Waiting after Grid Failure
Each time the utility grid voltage is disconnected from the HPC-250HT or the power supply is
disconnected from the MCU of the HPC-250HT, the system waits for additional five minutes
counting from the reconnection of the MCU power supply or counting from the moment in
which the stable condition of the utility network has been met, respectively, before the HPC-
250HT is allowed to connect to the utility grid again. Note, that the utility grid stability waiting
time can be in coincidence with the Automatic Start Up waiting time, but can not be
shortened or interrupted.
The conditions, in which the utility network can be considered stable can be defined on the
“Setting 2” tab page of the User Interface and are identified as “Nominal Grid Voltage”,
“Nominal Grid Frequency”, “Minimum Grid Voltage”, “Maximum Grid Voltage”, “Grid
Frequency Limit Fmax-Fnom” and “Grid Frequency Limit Fnom-Fmin”.
Being in this state, the remaining time until the utility network can be declared as stable is
continuously displayed in the User Interface “Status Bar”, in brackets next to the “Waiting
after Grid Failure” notification.
The system can get into this state
- From “Automatic Startup” state, by holding the Start/Stop Key Operated Spring
Return Switch in “Start” or “Stop” position for more than three seconds.
- From “Offline Mode”, if the previously defined stability conditions for the utility network
are not met.
- From “Connecting to Solar Arrays” state, if the previously defined stability conditions
for the utility network are not met
- Form “Waiting after Low Power Stop” state, if the previously defined stability
conditions for the utility network are not met
- Form “Testing of String Voltage” state, if the previously defined stability conditions for
the utility network are not met
The system can leave this state
- If the given time interval has passed after all the grid stability criterions have been
met - thus the grid is stable for the given time interval of 5 minutes - the system
proceeds to the “Connecting to Solar Arrays” state.
- If the disturbance in the measured grid parameters occurred in “Testing of String
Voltage” state, the system can get back to the “Testing of String Voltage” state if the
string voltage test time has not passed
- If the disturbance in the measured grid parameters occurred in “Testing of String
Voltage” state, the system can get to the “Grid Voltage and Frequency Test” state, if
the string voltage test time has already passed

USER MANUAL of HPC-250HT
PE07019-022-B Page 14 of 69
3.3.1.3 Testing of String Voltage
In thi state the HPC-250HT ascertains the sufficient level of DC voltage. This check is
performed by measuring the DC voltage level at the DC power input of the HPC-250HT until
sufficient DC voltage vs. time area was measured.
The time that has passed with the DC voltage level above the set threshold is continuously
indicated in brackets next to the “Start Time” value on the “Settings” tab page of the User
Interface and indicated on the Status bar In brackets, net to the “Testing of String Voltage”
text.
The system can get into this state
- From “Waiting after Low Power Stop“ state, if the time set in the “Wait Time” textbox
on the “Setting 1” tab page has passed.
- From “Waiting after Grid Failure” state if the necessary waiting time after the grid
failure has passed.
- From “Connecting to Solar Arrays” state after successful connection to the solar
arrays
The system can leave this state
- If the measured DC voltage level is above the voltage level set in the “Start Voltage”
[volts] textbox for the time duration set in the “Start Time” [seconds] textbox on the
“Setting 1” tab-page, and – after a regular, low-power shut down - the “Wait Time”
defined on the “Setting 1” tab page has passed, the system switches to “Grid Voltage
and Frequency Test” state
- By holding the Start / Stop Key Operated Spring-Return Switch (-S1) in “Stop”
condition for more than 3 seconds the system switches to “Shut Down” state

USER MANUAL of HPC-250HT
PE07019-022-B Page 15 of 69
3.3.1.4 Grid Voltage and Frequency Test
During this step several measurements are undertaken to safely decide the operating
conditions of the utility grid the HPC-250HT cabinet is connected to. Only after the connected
utility grid is in stable state - with its key properties within standard-defined ranges - may the
HPC-250HT proceed with preparations of grid connection.
The standard-defined ranges can be individually set to align on the local conditions and
regulations on the “Setting 2” tab page of the User Interface.
Modifiable grid parameters are
- nominal voltage
- range of voltage level deviation from nominal value in two directions separately
- frequency
- range of frequency deviation from nominal value in two directions separately
The system can get into this state
- From “Testing of String Voltage” state if the start conditions defined on the “Setting 1”
tab page have been met.
The system can leave this state
- After all of the grid parameters have been identified and are in the pre-defined ranges
as set on the “Setting 2” tab-page, the system switches to “Connecting to Grid, Test
of String Voltage” state
- By holding the Start / Stop Key Operated Spring-Return Switch (-S1) in “Stop”
condition for more than three seconds the system switches to the “Shut Down” state

USER MANUAL of HPC-250HT
PE07019-022-B Page 16 of 69
3.3.1.5 Connecting to Solar Arrays
The HPC-250HT DC side circuit breaker is a motor driven automatically operated DC circuit
breaker with two turn-on cycle states as follows
- Recharge of the actuating spring
- Turn On circuit breaker
The motor driven automatically operated DC circuit breaker isolates the 3 phase inverter (-A1)
from the DC EMC filter (-A11), the input DC fuses (optional) (-F1…-F16) and the network of
solar panels.
The system can get into this state
- After 5 minutes counting from entering “Automatic Startup State”, the system is
leaving „Automatic Startup” state automatically and steps into “Connecting to Solar
Arrays” state.
- Form “Waiting after Grid Failure” state, if the given time interval has passed after all
the grid stability criterions have been met - thus the grid is stable for the given time
interval of 5 minutes - the system proceeds to the “Connecting to Solar Arrays” state.
The system can leave this state
- The system switches to ”Testing of String Voltage” state if the utility grid operation
conditions set on the “Setting 2” tab page are met and the HPC-250HT did not
perform a regular low-power shut down, or, the “Wait Time” accessible on the “Setting
1” tab page is set to zero.
- The system switches to ”Waiting after Low Power Stop” state if the utility grid
operation conditions set on the “Setting 2” tab page are met and the HPC-250HT did
perform a regular low-power shut down and the “Wait Time” accessible on the
“Setting 1” tab page is not set to zero.
- The system switches to ”Waiting after Grid failure” state if the utility grid operation
conditions set on the “Setting 2” tab page are not met

USER MANUAL of HPC-250HT
PE07019-022-B Page 17 of 69
3.3.1.6 Connecting to Grid, Test of String Voltage
The output power delivery capability of the network of solar arrays is tested in this step of the
HPC-250HT start sequence. The network of solar arrays is loaded and input voltage drop is
measured. The measured voltage level (factory-determined voltage level, always below the
value set in the “Start Voltage” textbox on the “Setting 1” tab page) on the input of the HPC-
250HT determines the next step of the start sequence.
The system can get into this state
- From the “Grid Voltage and Frequency Test” state if the utility network parameters
are within the ranges defined on the “Setting 2” tab page.
The system can leave this state
- If the measured input voltage level of the HPC-250HT during the String Voltage Test
is above a factory-set safety value, the AC Contactor (-K1) turns ON, the system
connects to the utility network and system state switches to “Feeding to the Grid”
- If the measured input voltage level of the HPC-250HT during the String Voltage Test
is below a factory-set safety value, the system state switches to “Waiting after Low
power Stop”
- By holding the Start / Stop Key Operated Spring-Return Switch (-S1) in “Stop”
condition for more than three seconds the system switches to “Shut Down” state

USER MANUAL of HPC-250HT
PE07019-022-B Page 18 of 69
3.3.1.7 Feeding to the Grid (4)
After synchronization of the inverter output voltage and frequency value to the corresponding
measured values on the utility grid the AC Contactor (-K1) is turned ON to perform inverter-
to-grid connection. In the moment of connection the equipments and devices on both ends of
the AC Contactor (-K1) are energized and are operating on the same voltage and frequency
levels, therefore assuring a zero-current switch on of the contactor.
After successful completion of the start sequence the state of the HPC-250HT changes to
“Feeding to the Grid”, the system behaves according to the Maximum Power Point and
“Maximum Output Power” settings on the “Online Info” and the “Setting 2” tab page.
At first, in case MPP is activated on the “Online Info” tab page, after every successful grid
connection the system automatically performs one MPP scanning cycle.
After determining the current optimal power point the HPC-250HT is able to
- Reside in grid connected state and deliver power to the utility according to the
previously found maximum power point (MPP OFF)
- Search for new maximum power points at time intervals defined by “Scan Delay”
[seconds] on the “Online Info” tab-page. (MPP)
- Track the last found optimal power point (MPP Tracking)
- Track the previously found maximum power point and perform a new MPP search
after every set time interval defined in “”Scan Delay” [seconds] on the “Online Info”
tab page (MPP with Tracking)
- Feed back power not exceeding the value defined by “Maximum Output Power”
[percentage, Nominal Power = 100%] on the “Settings” tab-page.
A maximum power point scanning cycle can be initiated any time by tapping the “Start MPP
Scan” button on the “Online Info” tab page.
The time that has passed with the Output Power level above the set threshold is continuously
indicated in brackets next to the “Stop Time” value on the “Settings” tab page of the User
Interface.

USER MANUAL of HPC-250HT
PE07019-022-B Page 19 of 69
The system can get into this state
- If the measured input voltage level of the HPC-250HT during the String Voltage Test
is above a factory-set safety value, the AC Contactor (-K1) turns ON, the system
connects to the utility network and system state switches to “Feeding to the Grid”
The system can leave this state
- By holding the Start / Stop Key Operated Spring-Return Switch (-S1) in “Stop”
condition for more than three seconds the system switches to “Shut Down” state
- If the measured DC power falls below the value set in “Stop Power” [kW] for an
interval defined in “Stop Time” [seconds], both located on the “Settings” tab-page the
system switches to “Shut Down” state. In this case, however, a time interval -
equivalent to the one set in the “Wait Time” textbox on the “Setting 1” tab page – has
to pass before a new, automatic start up sequence is initiated by the system.

USER MANUAL of HPC-250HT
PE07019-022-B Page 20 of 69
3.3.1.8 Shut Down (5)
The system or the user initiates and performs a regular shut down sequence consisting of
actual system-state-defined steps, if one of the following requirements is met.
The system can get into this state
- If the Start / Stop Key Operated Spring-return Switch (-S1) is operated and held in the
“Stop” position for more than three seconds
- After an automatic shutdown process was initiated, meaning that the input DC power
of the HPC250-HT is lower than the threshold value set in the “Stop Power” [kW]
textbox for the time interval set in the “Stop Time” [seconds] textbox on the “Settings”
tab page.
The system can leave this state,
- And - depending on the state of the system in the moment of an incoming shut-down
request the system - automatically jumps over to one of the following states:
oWaiting after Grid Failure -> Offline
oWaiting after Low Power Stop -> Offline
oTesting of String Voltage - > Offline
oGrid Voltage and Frequency Test ->Offline
oConnecting to Grid, Test of String Voltage -> Shut Down