1.3 OPERATION
Four operating modes are provided. To switch from one mode to another, press the mode push button till
you reach the required operating mode and then wait for 2 seconds for the operating mode to be applied.
Following is description of the operating modes:
• OFF: In this mode the module cuts power completely from the load.
• AUTO: In MGG and MG installation, the module monitors the Utility supply. When the Utility fails or
its contactor fails to engage, the module counts a “Response” delaybefore starting the genset.
In GG installation, the module monitors the remote control input. When the remote control input becomes
active, the module counts a“Response” delay before starting the genset.
The genset is started only if it is in Ready mode
In MGG and GG installation:
o For ATS type: Following a mains failure, G1 or G2 is started depending on the “Alternate hrs”after
a “Response”delay. Load is engaged after the elapse of the “Warm-up” delay.
If “Alternate hrs”is set to a value of hours, the genset with the less number of run hours is started.
If “Alternate hrs”is set to G1/G2, G1/G2 is started.
Once a genset is feeding the load, it keeps feeding it for the number of hours set in “Alternate hrs”.
o For ATSO type: Following a mains failure, G1 (the smaller genset) or G2 (the bigger genset) is started
depending on the “Req priority”after a “Response” delay. Load is engaged after the elapse of the
“Warm-up” delay.
If the “Req priority” is set to Ld, G2 is requested if the load prior to mains failure was above the“G1 Max
Load %”, Otherwise, G1 is requested. The value of the load supplied by the Mains is retained for 5
minutes only. So if 5 minutes have elapsed from the mains failure, G2 is started always. This could occur
when switching to AUTO mode from Mains or OFF modes.
If the “Req priority” is set to G1/G2, G1/G2 is requested independently from Load.
If G1 is feeding the load and the current goes above the “G1 Max Load %”for a“G1 MaxLd del”delay, G2
is requested. If G2 is feeding the load and the current goes below the“G2 Min Load %”for a“G2 MinLd
del”delay, G1 is requested.
When the Mains is re-established, the power is switched back with a dead transfer time“Transfer”after a
restoration delay “Mains Rest.”and the genset is shut down after the elapse of the“Cooling”time. For
MGG and GG installation, in case the requested genset fails to start or its contactor fails to engage or it
shuts down due to any fault, the other genset will automatically start and supply the load. If the “Hold
Start”is enabled, and in case the genset failed to start, the start signal remains on so that when it
restarts, it will feed the load after disengaging the running genset. When the“Hold Start” is disabled, the
start signal is removed. Manual reset is required to recover from this failure. Please refer to section 2 for
display description.
• Mains: The module monitors the Mains supply. The load is fed exclusively from this supply if it is within the
acceptable limits. No gensets will be started if the Mains fails.
• G1: In this mode, G2 is always in standby mode. G1 is started when it is in ready modeand the Mains
fails.
• G2: In this mode, G2 is always in standby mode. G1 is started when it is in ready modeand the Mains
fails.
In case contactors are used for the transfer switch, each contactor is controlled by one dry contact. The
other dry contact is used as an alarm output (CxD.NO).
If motorized circuit breakers or changeover switches are used, each motorized breaker/ switch is controlled
by two relays. The rst has one normally open dry contact (CxENG) and is used to engage the motorized
circuit by giving a pulse of 2 seconds, the second is controlled by a contact that has a common (CxC),
normally open (CxD.NO) and normally closed (CxD.NC) contacts to disengage the motorized circuit breaker
by giving a pulse of 4 seconds.
1 .GENERAL DESCRIPTION
Presettable in the menu. Refer to Section 2.4
Refer to Section 2.5
