8GE Zenith Controls ■
ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)
User Setting for Voltage & Frequency

Standard 3-Phase Sensing

on 3 and 4 Pole Units

Source 1

Under Voltage "Restore"
Factory Default: 90%
This adjustment determines the minimum acceptable
voltage required to transfer to Source 1.
Adjust via the SET menu. Range is 85% to 100% in
1% increments (see page 17).
Once satisfied, the T timer will begin timing
to transfer to Source 1.
Under Voltage "Fail"
Factory Default: 80%
This adjustment determines the low voltage threshold.
Adjust via the SET menu. Range is 75% to 98% in 1%
increments (see page 17).
"Fail" must be a minimum of 2 % below "Restore"
setting. Once voltage falls below threshold, P timer
begins timing to signal Source 2 Generator to start.
Under Frequency "Restore"
Factory Default: 95%
This adjustment determines the minimum acceptable
frequency required to transfer to Source 1.
Adjust via the SET menu. Range is 90% to 100% in
1% increments (see page 17).
Once satisfied, the T timer will begin timing
to transfer to Source 1.
Under Frequency "Fail"
Factory Default: 90%, (5 seconds minimum).
This adjustment determines the low frequency threshold.
Adjust via the SET menu. Range is 88% to 98% in 1%
increments (see page 17).
"Fail" must be a minimum of 2 % below "Restore"
setting. Once satisfied, the T timer will begin timing to
transfer to Source 1.
Over Frequency "Restore"
Factory Default: 102%
This adjustment determines the minimum acceptable
Over Frequency threshold at which the transfer switch
is allowed to re-transfer to Source 1.
Adjust via the SET menu. Range is 102% to 104% in
1% increments (see page 17). “Restore” must be a
minimum of 1% below “Fail” setting.
Over Frequency "Fail"
Factory Default: 105%
This adjustment determines the maximum acceptable
Over Frequency.
Adjust via the SET menu. Range is 103% to 105% in 1%
increments (see page 17).Once exceeded, the P timer
begins timing to signal the generator to start.

Source 2

Under Voltage "Restore"
Factory Default: 90%
This adjustment determines the minimum acceptable
voltage required to transfer to Source 2.
Adjust via the SET menu. Range is 85% to 100% in
1% increments (see page 17).
Once satisfied, the W timer will begin timing
to transfer to Source 2.
Under Voltage "Fail"
Factory Default: 80%
This adjustment determines the low voltage threshold.
Adjust via the SET menu. Range is 75% to 98% in 1%
increments (see page 17).
"Fail" must be a minimum of 2 % below "Restore"
setting. Once voltage falls below threshold, T timer
will be bypassed to expedite the transfer to Source 1.
Over Voltage "Fail"
Factory Default: 110%
This adjustment determines the maximum acceptable
Over Voltage. Adjust via the SET menu. Range is 105%
to 110% in 1% increments (see page 17). Once exceed-
ed, the T timer will be bypassed to expedite the transfer
to Source 1.
Over Voltage "Restore"
Factory Default: 105%
This adjustment determines the minimum acceptable
Over Voltage threshold at which the transfer switch is
allowed to transfer to Source 2. Adjust via the SET
menu. Range is 103% to 105% in 1% increments
(see page 17). “Restore” must be a minimum of
2% below “Fail” setting.
Under Frequency "Restore"
Factory Default: 95%
This adjustment determines the minimum acceptable
frequency required to transfer to Source 2.
Adjust via the SET menu. Range is 90% to 100% in
1% increments (see page 17).
Once satisfied, the W timer will begin timing
to transfer to Source 2.
Under Frequency "Fail"
Factory Default: 90%, (5 seconds minimum).
This adjustment determines the low frequency threshold.
Adjust via the SET menu. Range is 88% to 98% in
1% increments (see page 17).
"Fail" must be a minimum of 2 % below "Restore" setting.
Once satisfied, the W timer will begin timing to transfer
to Source 2.
Over Frequency "Fail"
Factory Default: 105%
This adjustment determines the maximum acceptable
Over Frequency. Adjust via the SET menu. Range is
103% to 105% in 1% increments (see page 17). Once
exceeded, the T timer will be bypassed to expedite the
transfer to Source 1.
Over Frequency "Restore"
Factory Default: 102%
This adjustment determines the minimum acceptable
Over Frequency threshold at which the transfer switch
is allowed to re-transfer to Source 2. Adjust via the SET
menu. Range is 102% to 104% in 1% increments
(see page 17). “Restore” must be a minimum of
1% below “Fail” setting.