67
66
Discrimination with ‘T’ type fuses
The following table should be used as a guide when selecting Terasaki
Tempower2
Air Circuit Breakers and fuses (BS88/
IEC269) which are immediately downstream from a transformer.
In and I
R
are set to the full rated current of the transformer, and t
R
, Isd and tsd are at standard transformer settings.
Listed are the maximum fuse ratings that can be used when downstream from a given ACB at these settings.
Also included are the maximum fuse ratings that can be used downstream when t
R
, Isd and tsd are at their maximum settings.
All information listed is based on a transformer secondary voltage of 415V.
> The above ‘In’ settings are based on 100% of Rated Current (Ict).
> Table Reference : I
R
- Long Time Delay Pickup Current, t
R
- Long Time Delay Time Setting, Isd - Short Time Delay Pickup Current, tsd - Short Time Delay Time Setting.
Notes:
Note:1 It is possible to increase the maximum fuse rating by utilising the ‘ramp’ facility on the on the
TemPower2
Protection Relay (AGR).
Note:2 Information on fuses above 1250A rating was not available.
Note:3 All ACBs have Ii (Instantanious) set to NON. (MCR can be set to ON)
Please note the above table is meant only for guidance, individual installations should have a specific discrimination study undertaken.
The
TemTransfer
is a fully configurable Automatic Changeover Controller (ACC). It is designed to monitor the incoming AC
mains supply (1 or 3 phases) for under/over voltage and under/over frequency. Should these fall out of limits, the module will
issue a start command to the generating set controller. Once the set is available and producing an output within limits the ACC
will control the transfer devices and switch the load from the mains to the generating set. Should the mains supply return to
within limits the module will command a return to the mains supply and shut down the generator after a suitable cooling run.
Various timing sequences are used to prevent nuisance starting and supply breaks.
TemTransfer
is compatible with
TemPower2 ACB
s,
TemBreak2 MCCB
s and
TemContact
contactors.
Terasaki can supply
TemTransfer
pre-configured to specification, or unconfigured with an optional interface kit.
Configuration is by PC based software and the interface kit using an FCC68 socket on the rear of the module. This allows
rapid and secure configuration of the module. The FCC68 socket also provides full real-time diagnostics on the status of the
ACC, its inputs and outputs.
Configuration and connection options allow for a wide range of higher functions such as
‘Auto start inhibit’, ‘Manual restore to
mains’, ‘Load inhibit’
(both mains and gen-set)
, ‘Lamp test’, Push-button transfer control, External mains or Gen-set failure inputs,
etc.
The four position key-switch allows for mode selection:-
• Auto Mode
• Auto mode with manual return to Mains
• Run generator off load
• Run generator on load
A clear mimic diagram with ‘International’ symbols and LEDs provide clear
indication of supply availability and load switching status. Further LED
indication is provided for ‘Start delay in progress’ and ‘Mains return timer
active’. Two user configurable LED’s are provided to allow the user to display
specific states (defaulted to indicate that the closing procedure of the Mains
or Generator circuit breaker has been started).
Five user configurable relays are provided to allow control of contactors,
different circuit breaker types and engine control modules and alarm
systems.
The controller features a self seeking power supply which will utilise power
from the Mains AC supply or the Generator AC supply. A DC supply to the module is not essential for basic operation, though
some ‘higher’ functions require it (such as system diagnostics).
The module is mounted in a robust plastic case, connection to the module is via plug and socket connectors.
Accessories For Dual Supply Changeover Systems Accessories
TemTransfer
Automatic Changeover Controller
Application Data
7
