Tescom STS 1000A 3 Pole, User Manual

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► OPTIONS MENU
This menu contains operating modes and user-configurable parameters. A USER PASSWORD is required to
enter the OPTIONS MENU , so as to protect these parameters. The default value of USER PSW is 0000
The following parameters are configurable.
PREFERRED: Source 1 or 2
The + or – keys are used to select one of the two input sources as the preferred source.
In normal operating conditions, if a preference is assigned to one of the two sources, the STS powers the load
from the preferred source, considering it as the preferred source. If the preferred source is good, the load is
always powered from that source. If at any time that source goes out of the accepted range, and is therefore
no longer good, the STS transfers the load onto the alternative power source.
R-XFER: (ON or OFF)
The + or – keys are used to decide whether to enable or disable the re-transfer.
After switching has occurred for any reason, the user can decide whether to re-transfer the load back onto the
preferred source or to remain in that situation until the alternative power source returns within the accepted
range.
If re-transfer is enabled, this takes place after a delay set by the user (REX-DELAY from 016 to 127 sec).
D.R-XFER: 016 sec
(how long the STS stays on the alternative source)
This submenu can be used to set the time of the delay before re-transferring from the alternative mains supply
to the one selected as the preferred source. The + or – keys can be used to increase or decrease the interval
of time before a re-transfer. The interval of time can be set from 016 to 127 seconds.
OVLOAD: (ENABLE or DISABLE)
The user can select the kind of behaviour to be followed by the STS in an overload condition.
ENABLE : in this configuration the electronic overload control is enabled.
The STS powers the load with a specific overload current value for a specific period of time only, according to
the overload value, after which the SCR opens and the load is switched off.
DISABLE : in this configuration the electronic overload control is disabled, thus the STS continues to power the
load with any current value.
The current value is limited exclusively by the magneto-thermal switch (MCCB) on the input.
AL HOLD: 010 sec
The + or – keys can be used to increase or decrease the duration of an alarm from a minimum of 8 sec to a
maximum of 64 sec. (default value 10 sec.)
NSYNC.TR: (0-curr, Delay, Disable)
The user can select the kind of behaviour to be followed by the STS in the event of a transfer with the two input
sources out of sync.
If the two sources are not synchronised
, the transfer can take place in three different user configurable ways:
- 0 CURR. (transfer with zero current): the transfer takes place when the output current goes to zero
(method used for synchronised switching).
- DELAY (transfer with delay time): the transfer can only take place after a safety delay time that can be set
by the user, during this period the load is not powered.
The time delay can be set via the ADJUST MENU described below (from 20 to 255msec) default value
24msec.
- DISABLE (transfer disabled): the transfer is not performed for non-synchronised sources.
If the preferred source goes out of the accepted limits while the two sources are not synchronised, the STS will
not perform the transfer and the load will be lost.
OVL.RESET: (AUTO or MANUAL)
After an overload with the electronic control enabled, which thus causes the SCRs to open and the subsequent
loss of the load, the user can decide to automatically or manually reset the overload alarm.
AUTO the overload alarm is automatically reset and at the end of the “alarm hold time” the STS goes back to
powering the load.
MANUAL the STS no longer powers the load until the overload alarm is manually reset via command ENTR-
INHIBIT RST from the COMMANDS MENU.