Instruction Leaflet
30-470 (E)
Page 7
Table 1 Interrupting, Closing and Withstand Rating
Robonic Type A
Robonic
Continuous
rms symmetrical amperes
Rating
600 Vac
480 Vac
120,208,240 Vac
30 to 100 amps
14,000
14,000
18,000
150 to 1000 amps
22,000
30,000
42,000
1200 to 3000 amps
100,000
100,000
125,000
Since type A Robonics employ magnetic only breakers, their interrupting,
closing, and withstand ratings are the same value. Under fault
conditions, with its normal breaker closed, a Robonic is required to
withstand the energy let through of the normal service protective
device while the fault is being cleared. At the same time, should the
normal voltage fall below the voltage sensing relays selected value,
and if the alternate source were available, the Robonic could transfer
before the normal service protective device cleared the fault.
This would require that the Robonic be capable of interrupting the
protective devices let through current. In addition, the Robonic could
be required to close in on a fault. Thus can be seen the need for
Robonics to have, interrupting, closing and withstand ratings.
The interrupting, closing and withstand ratings shown in Table 1 are
those for standard type A Robonics. For higher values, consideration
can be given to use of Robonics built with Mark 75, Tri-Pac or SCB
breakers.
Table 2 Maximum Upstream Circuit Protective Devices for
Type A Robonics, All Classes of Loads
Standard Robonic Maximum Upstream Maximum Upstream Fuse Rating
Continuous
Breaker Frame Size
Rating (amperes)
Class J or L
Class K5 or R
30, 70, 100
EHB, FB, FB-P
100
100
150, 225
CA, JA, KA
225
225
400
DA, LB, LA-P
400
400
600
LA600
600
600
800
MA, MC, NB-P
800
800
1000, 1200
NB, NC
1200
....
1400, 2000
PB, PB-P, PCC
2000
....
Table 3 Maximum Upstream Circuit Protective Device for
Type A Robonics, 90% or Larger Motor Load
Standard Robonic
Maximum Upstream
Maximum Upstream Fuse Rating
Continuous
Breaker Frame Size
Rating (amperes)
Class J or L Class K5 or R
30, 70, 100
EHB,FB,HFB,FB-P
300
100
LA-P,c/w 400 LAP10
150, 225
CA,JA,KA,HKA,LA
400
225
HLA,LB,HLB,MA,NB
LA-P,NB-P c/w 1000
NB14 MC,NC
400
LA,HCA,LA-P,LB,MA
600
400
HMA,NB,HNB,NB-P
MC,HMC,NC,HNC
600
MA,HMA,MC,HMC
1200
600
NB,NC,HNC,NB-P
800
MA,HMA,NB,HNB,
1200
....
NB-P
MC,HMC,NC,HNC
1000
NB,HNB,NC,HNC,PB-P
1200
....
1200
NB,HNB,NC,HNC,PB-P
1200
....
1400, 2000
PB,PB-P,PC
2000
....
Automatic Control
Voltage Sensing Relays
Ratings 1.0 volt-ampere power consumption
Input Coil Voltage 120 volts at 50/60 hertz
Contact Rating 3.0 amperes resistive at 120 volts
Duty continuous
Operating Temperature Ratings -10°C to +55°C
Description
The device VS is an octual plug-in unit complete with solid-state
sensing and a DPDT relay enclosed in a dust-tight, yellow capsule.
The receptacles and plugs are designed to ensure a tight fit to reduce
the possibility of coming loose through vibrations.
The solid state sensing of the fixed model has been factory set for
pickup and dropout values of 104 volts Ac and 84 volts Ac respectively.
The adjustable model voltage sensor has a variable range of pickup,
92 volts to 140 volts Ac and dropout, 90 volts to 138 volts Ac with a
close differential of 2 volts.
The contacts being two pole double throw allows one set to be
incorporated in the control scheme and an additional set for external
connections if required.
Application
When used on the Robonic Automatic Transfer Switch as an under-
voltage sensing device, they have been designated as devices VS.
The standard Robonic Transfer Switch comes with one fixed voltage
sensor, VS1, for single phase application and three fixed voltage
sensors, VS1, VS2 and VS3, for three phase applications, all of
which monitor the normal power source only.
The single phase voltage sensor is connected to the normal control
transformer, NT, to monitor the normal source.
The three phase voltage sensors are connected to three smaller
transformers, VST, which are connected in a delta-Wye configuration
for use on all voltages, including 120/208 volts, none of which use the
system neutral.