2. System settings
2.10. Power management
2.10.1. General PM Parameter
This group comprises the general settings for power management.
[0180. Generator – number:]
Number of generator. This number is shown in the main page and is used by the power manager for all event histories to show the user which generator has been started and stopped.
[0181. – priority:]
Priority of the diesel generator. The priority is used to define the start and stop sequence for the power management. The priority is shown in the main page. The priority can also be changed on the load page or over Modbus communication if Parameter [0192] is OFF.
[0182. Net selector –1.Event:]
[0183. Net selector –2.Event:]
The net selectors define the bus bar section to which the circuit breaker of the corresponding generator has been connected. A maximum of four bus bar sections can be recognized. Example: 0189.Load balance after start: 10sec 0190.Mains parallel operation: 0 0191.Manual mode type : MANUAL 1 0192.Priority select by event: 504 0193. – 1.event: 519 0194. – 2.event: 521 0195. – 3.event: 0 0196. – 4.event: 0 0197.Remain in manual : NO 0198.Secure front key access : 512 0199.reserved :
2400.Nominal power reduction : CURR.3 2401. – Pn zero scale point: 70.0 % 2402. – scale adjustment : 100.0 % 2403.Request own power by : 0 2404. – power not avail.event
2405.Preselect prio. by event: 0
If a bus tie breaker is in use, the user can link the auxiliary output of the bus tie breaker with a function input. The event number of this function input has to be used for the net selector parameter to define the bus bar sections.
Net selectors
183 182 Net
inactive inactive 0
inactive active 1
active inactive 2 active active 3
[0184. Automatic mode :]
Automatic mode release. An event number is used to release the automatic mode (e.g. via a function input).
Example:
A function input is used to release the automatic mode. If the function input is active, the automatic mode will be automatically set and the user can switch between automatic and manual. If the function input is inactive, the manual mode is fixed and blocked.
Event numbers linked to the modes:
2905 = Manual mode, 2906 = Automatic mode.
[0185. Start release :]
Start release of the aggregate. The user can activate an event number to allow the starting of the aggregate (e.g. via a function input).
Example:
The user can activate a function input to allow the starting. If the function input is active, the starting of the aggregate is allowed. If the function input is inactive, all start orders will be blocked and the device will switch to fixed manual mode. In this case Event [0185] (“start block”) will become active. Use this event for an alarm message.
[0186. Start next diesel by :]
The user can start the next aggregate from the start list by event.
Example:
The user can activate a function input to start an aggregate which is next in the stand-by sequence. If the state of the function input changes to active, this aggregate will be started. Only this trigger condition starts the aggregate.
[0187. Remote Start :]
The user can start the own aggregate from remote by an event.
Example:
The user can activate a function input to start the “own” aggregate from remote. If the state of the function input changes to active, the “own” aggregate will be started. Only this trigger condition starts the aggregate.
[0188. Remote Stop :]
The user can stop the “own” aggregate from remote by an event.
Example:
The user can activate a function input to stop the “own” aggregate from remote. If the state of the function input changes to active, the “own” aggregate will be stopped. Only this trigger condition stops the aggregate.
[0189. Load balance after start:]
If the power management starts a diesel generator (e.g. big consumer request), then after the circuit breaker is switched on, the process will be delayed to balance the load before the next action from the power manager happens (e.g. big consumer release).
[0190. Mains parallel operation:]
In case of mains parallel operation, some regulators (e.g. asymmetric load control) have other conditions. With this event number (e.g. function input), the system recognizes mains parallel or insulated operation.
[0191. Manual mode type:]
There are several manual mode types available:
[0192.Priority select by event]
With this event the selectors can be enabled. It is not possible to change the priority over another source (e.g. load page or communication) if the selectors are enabled.
[0193. – 1. event]
[0194. – 2. event]
[0195. – 3. event]
[0196. – 4. event]
With the four events (e.g. from binary inputs) a priority can be selected:
PRIORITY SELECTORS
AUTOMATIC / MANUAL MODE FUNCTIONS
MANUAL MODE
[0197. Remain in manual ]
This parameter controls the trigger of the automatic mode:
• NO: After an alarm with priority disappears, the mode will switch back to automatic (if automatic was active before the alarm). The mode is stored nonvolatile.
• YES: After system start or if an alarm with priority disappears, the mode will always remain in manual.
[0198. Secure front key access]
With this parameter the access to the START / STOP / AUTO / MANU. – front keys can be protected with an password (also the Load page – Command window).
• Event inactive: free access to the keys.
• Event active: the keys are protected with Code #1 (see Chapter 2.1.). The keys are released for 30 seconds after the right password is entered.
[2400. Nominal power reduction]
The nominal power reduction can be used for shaft generator operation.
This parameter enables the function and selects an analog input (see Chapter 2.5.).
The analog input must be also enabled:
• Function: 0--20 or 4--20 mA.
• Measuring type: mA
• Full scale: sets the upper cutoff point of the current signal (e.g. 16.8 mA).
• Zero scale: sets the lower cutoff point of the current signal (e.g. 5.8 mA).
[2401. – Pn zero scale point ]
Defines the lowest power value for the nominal power reduction (e.g. 40.0 %).
Note: the upper value is always 100.0 %.
[2402. – scale adjustment ]
Linear calibration of the mA-scale between the full and the zero scale. This parameter is normally set to 100.0%.
The following graph shows an example for the nominal power reduction:
Figure: Nominal power reduction
Note: On the analog inputs page (MENU: DISPLAY – METERS), the following nominal power reduction values are shown:
• The actual mA value.
• The reduced nominal power in % and in kW.
Pn [%]
5.8 16.8 mA
40.0 100.0
[2403. Request own power by]
This function can be used to request the own actual power (in kW) from the net, before the own generator is stopped.
The event from parameter 2403 activates the request. The function will calculate the load situation in the own net, without the power of the own generator (assuming that the own gen. should be stop). If the future net power reserve is insufficient, the function will start one or more standby gen. Finally, if the power reserve is available, event 2403 will be activated. This event can be used to trigger a stop (e.g. over parameter 188).
[2404. – power not avail. event]
This event is related to the function from parameter 2403. If it is not possible to provide the requested own power from the net (e.g. there are no standbys), this event will be activated. It can be used to trigger an alarm.
[2405. Preselect prio. by event]
[2406. - priority]
If the event set on P2405 changes from inactive to active, the priority will be set once to the value of P2406.
2.10.2. Power management
The power management parameters offers two main functionallities (philosophies) for the load-depending starting and stopping within a bus bar section. Each function can be activated independently of the other one (but it is advisable to decide for only one).
• The first function (P900-917) is operating on several limits for starting and stopping (classical P.M.).
• Within the second function (P2430-2449), up to eight load ranges can be defined. For every load range a combination of up to five gen. (priorities) can be defined, which should be connected to the bus bar. The system will manage to start and/or stop the gen.
according to the load ranges.
POWER MANAGEMENT 0916.Stop without runn.down : NO 0917.Block own start by event: 0
[0900. P.M. – switch by event:]
Event switch for the first power management function. This switch affects only the parameters 901-917. All devices in one net must have this switch enabled for activation!
[0901. – characteristic :]
Switch characteristic of power management ON/OFF switch Parameter [0900]:
ON -> OFF: If event of PM-switch is active, power management will be switched off.
OFF -> ON: If event of PM-switch is active, power management will be switched on.
[0902. START – check limits :]
Checking single or average start limits. This parameter is valid for [0903], [0905] and [0909]. All limits can be disabled by setting them to zero.
SINGLE: When passing limit parameters [0903], [0905] or [0909] the start order will be given depending on the load / current of each diesel engine. If a generator passes the limit while the others do not, a start order will be given.
AVERAGE: Start order given if average load / current of Parameter [0903], [0905] or [0909] is passed. Average load / current means the average of load / current of all diesel engines running on the mains in one net.
[0903. – 1. load limit :]
First start limit for load-depending start of an additional diesel engine.
[0904. – delay :]
Delay time for first start limit Parameter [0903].
[0905. – 2.load limit :]
Second start limit for load-depending start of an additional diesel engine.
[0906. – delay :]
Delay time for second start limit Parameter [0905].
[0907. – low frequency:]
Passage of a low frequency limit also starts a diesel engine. Coordinate with Parameters [2007] and [2010].
[0908. – delay :]
Delay time for low frequency start limit Parameter [0907].
[0909. – high current :]
Start limit for current-depending start of an additional diesel engine.
[0910. – delay :]
Delay time for current start limit Parameter [0909].
[0911. STOP – with priority :]
Sequence for stop order.
LOW: Load-depending stop works in a sequence so that the aggregate with the lowest priority will be stopped first.
HIGH:: Load-depending stop works in a sequence so that the aggregate with the highest priority will be stopped first.
[0912. – block by event :]
By activating this event on any device in one net, load-depending stop of the diesel engines can be blocked (this affects also the second P.M. function (P2430-2449).
[0913. – remaining load :]
Stop limit for load-depending stop of operating diesel engine. The entered percentage limit is the load value remaining on the mains after disconnecting the diesel engine.
[0914. – remaining curr.:]
Stop limit for current-depending stop of operating diesel engine. The entered percentage limit is the current value remaining on the mains after disconnecting the diesel engine. If zero is setted, the limitcheck will be disabled.
[0915. – delay :]
Delay time for current and load stop limit Parameters [0913] and [0914]. Note that both conditions must be fullfilled to start the delay. If only load stop is to be used, the current limit (914) must be set to zero. Both limits can be disabled by setting them to zero, if PM-stop is not to be used. Current PM-stop [914] is only available in connection with load PM-stop, never alone.
[0916. Stop without runn. down]
If this parameter is set to “YES”, the stopped gen. will only open the CB (after load reduction), and than remain running.
[0917. Block own start by event]
By activating this event, the start of the own diesel engine through the power management system can be blocked. The blocking does not affect other start sources (e.g. blackout, start next…). A message will be displayed on the power management page if the blocking is active.
[2430. LOAD RANGES – by event]
Event switch for the second power management function. This switch affects only the parameters 2431-2449. All devices in one net must have this switch enabled for activation!
[2431. – change to upper range]
If the actual net power changes from one range to a higher range, the higher range will be taken as the valid range after this delay time has passed.
[2432. – change to lower range]
If the actual net power changes from one range to a lower range, the lower range will be taken as the valid range after this delay time has passed.
[2432. – load range hysteresis]
This hysteresis is valid if the actual net power changes from one range to a higher range.
The power must fall below this hysteresis in order to return to the previous (lower) range.
[2434. – 1. load range]
[2435. – priority]
……
[2448. – 8. load range]
[2449. – priority]
With this parameters up to eight ranges can be defined. Each range starts at the previous range and ends at the setted kW value. For every range up to five gen. (identified in the net by the priorities) can be assigned, which should be connected to the bus bar.
Note: the starting and stopping will begin when a new range becomes valid (after the delays P2431 or 2432 are passed). The system will first start all the needed generators. After all the needed generators are connected to the bus bar, the system will begin to stop the unnecessary generators. If one generator needed for the actual load range is not available (in MANUAL and stopped), the system will search for another generator with the same nominal power. If the search is without result, the next standby generator will be started. The stopping is blocked in this case. The system will start or stop only generators which priority is defined in one of the load ranges (parameters 2435-2449).
The stopping is automaticallyblocked if the PM stop is blocked (see P912) or if a “big consumer request” is active in the net (see 2.10.7.).
If parameter 2430 is setted to a value greater than zero, an supervision becomes active. This supervision checks if all the gen. defined within the parameters 2435-2449 are available (in AUTOM.). In this case event 2430 will be active. Event 2431 will be active if P2430 is set (to a value greater zero) and the gen.
needed for the actual range are all in AUTOM.
This events can be used for alarming or to control processes (e.g. to switch to the classical PM if gen. are not available).