Emerson Series 300, ASCO 300 Series Operator's Manual

Operator’s

Manual

Series 300

Automatic Transfer Switches

H–desi g n 600 throu gh 1200 amps

DANGER is used in this manual to warn of high

voltages capable of causin g shock, burns, or death.

WARNINGisusedinthismanualtowarn

of possible personal injury.

CAUTIONisusedinthismanualtowarn

of possible equipment damage.

An experienced licensed electrician must install the A TS.

Refer to the outline and wiring drawings provided
with ASCO Series 300 ATS for installation details.

TABLE OF CONTENTS

section

INSTALLATION 1..........................

SEQUENCE OF OPERATION 2.............

TESTING & SERVICE 3....................

ADJUSTMENTS 4.........................

CONTROL FEATURES 5...................

INDEX back cover.........................

50 Hanover Road, Florham Park, New Jersey 07932–1591 USA
For sales or service call 1 800 800–2726 (ASCO) www.ascopower.com

ASCO POWER TECHNOLOGIES CANADA PO Box 1238, 17 Airport Road, Brantford, Ontario, Canada N3T 5T3
telephone [phone], fax [phone], for service call 1 888 234–2726 (ASCO) www.asco.ca

1200 amp. size600, 800, 1000 amp. sizes

381333–201 E

Nameplate

The Transfer Switch nameplate includes data for each
specific ASCO Series 300 ATS. Use the ATS only
within the limits shown on this nameplate.

H 300 B 3 600 N 1 C

Catalog Number Identification

A typical Catalog Number is shown below with its
elements explained. The example is for a Series 300
ATS with switched neutral, 3 pole, 600 amp, 480 V, in
a Type 1 enclosure:

B –switched
C – overlapping

blank – solid

neutral

connections

power

connections

Neutral

Phase Poles

2 –singleØ
3 –threeØ

Amperes Voltage Controller Enclosure

600

800
1000

1200

C 208

D 220
E 230

F 240

H 380

J 400

L 440

M 460
N 480

P 550

Q 575

R 600

1 –standard

1X –if

accessories

ordered

* available 600 – 1000 amp. sizes only

C –type1

F –type3R

G –type4 *

L –type12 *

blank – open type

K 415

Controller

membrane

controls

Transfer

Switch

terminal block TB

for engine start

and switch

position contacts

power

connections

neutral

connections

600 amp. size in typical enclosure with location of customer connections

ASCO Series 300 Automatic Transfer Switches (ATSs) are
Listed under Underwriters Laboratories UL 1008 Standard
for Safety for Automatic Transfer Switches. All control
features are UL Component Recognized, which assures that
ASCO automatic transfer switches meet OSHA Safety
Requ irem ents and will be acceptable to electrical inspectors.

ASCO Series 300 Automatic Transfer Switches are suitable
for emergency and standby system applications. They meet
emergency system rating requirements as defined in
National Electrical Code (NEC) Article 700 and UL 1008.
Also, they are suitable for the requirements of NEC Article
517 – Health Care Facilities, NEC Article 701 – Legally
Required Standby Systems, NEC Article 702 – Optiona l

neutral

connections

power

connections

Standby Systems, NFPA 99 Health Care Facilities, and
NFPA 110 Emergency and Standby Power Systems.

Rating Label

Each automatic transfer switch contains a rating label to
define the loads and fault circuit withstand / closing ratings.
Refer to the label on the transfer switch for specific values.

Do not exceed the values on the rating label.

Exceeding the rating can cause personal injury

or serious equipment damage.

Controller

Transfer

Switch

terminal block TB

for engine start

and switch

position contacts

power

connections

neutral

connections

membrane

controls

800 and 1000 amp. size in typical enclosure with location of customer connections

neutral

connections

power

connections

Transfer

Switch

Controller

membrane

controls

terminal block TB

for engine start

and switch

position contacts

power

connections

neutral

connections

1200 amp. size in typical enclosure with location of customer connections

SECTION 1 INSTALLATION

Series 300 Automatic Transfer Switches are factory wired
and tested. Installation requires skid removal then
securing the enclosure to the supporting foundation.

Remove the Shipping Skid

Open the front door and remove the four lag screws (2 in
front, 2 i n rear) securing enclosure to the wood skid.

Supporting Foundation

Testing Power Conductors

Do not connect the power conductors to the ASCO
Series 300 transfer switch until they are tested. Installing
power cables in conduit, cable troughs and ceiling-sus­pended hangers often requires considerable force. The
pulling of cables can damage insulation and stretch or
break the conductor’s strands. For this reason, after the
cables are pulled into position, and before
connected, they should be tested to verify that they are
not defective or have been damaged during installation.

they are

The supporting foundation for the enclosure must be
level and straight. Refer to the applicable enclosure
outline drawing included with the Series 300 for all
mounting details including door opening space.

If bottom cable entry is used, the foundation must be
prepared so that the conduit stubs are located correctly.
Refer to the enclosure outline drawingfor specifiedarea
and location. Provide cable bending space and clearance
to live metal parts. When a concrete floor is poured, use
interlocking conduit spacer caps or a wood or metal
template to maintain proper conduit alignment.

Mounting

Refer to the applicable enclosure outline drawing fur­nished with this switch and mount the Series 300
according to details and instructions shown on diagram.

Line Connections

Refer to the Wiring Diagram provided with your Series
300 ATS. All wiring must be made in accordance with the
National Electrical Code and local codes.

It is unnecessary to remove pole covers from the transfer
switch. If you do remove them, reinstall them carefully.

Protect the automatic transfer switch from

construction grit and metal chips to prevent

malfunction or shortened life of the ATS.

Connecting Power Conductors

After the power cables have been tested, connect them to
the appropriate terminal lugs on the transfer switch as
shown on the wiring diagram provided with this Series

300. M ake sure the lugs provided are suitable for use with
the cables being installed. Standard terminal lugs are
solderless screw type and will accept the wire sizes listed
on the drawings provided with the Series 300. Be careful
when stripping insulation from the cables; avoi d nicking
or ringing the conductor. Remove surface oxides from
cables by cleaning with a wire brush. When aluminum
cable is used, apply joint compound to conductors.
Tighten cable lugs to the torque specified on rating label.

Controller Ground

A grounding wire must be connected to the controller’s
lower left mounting stud. Because the controller is
mounted on the enclosure door, a conductive strap must
be used between the enclosure and the door. This
connection provides proper grounding which does not
rely upon the door hinges.

De–energize the conductors before making any
line or auxiliary circuitry connections. Be sure
that Normal and Emergency line connections
are in proper phase rotation. Place engine gen­erator starting control in the OFF position. Make
sure engine generator is not in operation.

Harnesses

The transfer switch is connected to the left side of the
controller by a plug–in harness (two plugs).

1 --- 1

INSTALLATION (continued)

Engine Starting Contacts

Customer connections for engine control contact and TS
auxiliary contacts connections are located on terminal
block TB which is mounted on the front lower left of the
transfer switch. Refer to wiring diagram provided with
the Series 300 A TS and connect the engine start wires to
the appropriate terminals. See Figure 1–1 and Table A.

TableA.Enginestart

connections.

When normal

source fails

Te r m i n a l s

on transfer

switch

contact closes TB1 and TB2
contact opens TB1 and TB3

Auxiliary Circuits

Connect auxiliary circuit wires to
appropriate terminals on transfer
switch terminal block TB as shown
on the wiring diagram provided
with this Series 300 Automatic
Transfer Switch. Make the neces­sary auxiliary connections by refer­ring to Section 5, Control Features.

Connections to Controller
for other Control Features

(located on bottom of Controller)

COMMON

FEATURE 7

closes to start

FEATURE 8

opens to start

COMMON

FEATURE 14B

closed o n emergency

FEATURE 14A

closed on normal

COMMON

FEATURE 14BA

closed o n emergency

FEATURE 14AA

closed on normal

terminal block for engine start and

auxiliary circuit connections

left side of

transfer switch

Engine Starting

Signals

5amps,32VDC

5ampsresistive28VDC

or 120 V AC max.

TS Auxiliary Contacts

Feature 14A & 14B

10 amps, 32 V DC

10 amps 250 V AC

general purpose

Optional

TS Auxiliary Contacts

Feature 14AA & 14BA

10 amps, 32 V DC
10 amps 250 V AC

general purpose

Figure 1-1. Engine start and auxiliary circuit

terminal block TB located on the transfer switch.

Load Disconnect

Feature

Connections

(see Wiring Diagram

& refer to page 5–4

for DIP switch settings)

Programmable

Engine Exerciser

connection,

if provided

(refer to

page 5–3)

Remote Control Features Connections

(refer to the Wiring Diagram &

page 5–4 for DIP switch settings)

Each control contact must be suitable

for a 5 V DC low energy circuit.

for factory

use only

Figure 1-2. Input / output label on the Controller showing possible connections to the lower terminal block.

1 --- 2

INSTALLATION (continued)

Functional Test

The Functional Test consists of three checks: manual
operation, voltage checks, and electrical operation.

Do these checks in the order presented to

avoid damaging the automatic transfer switch.

Read all instructions on the Wiring Diagram and labels
affixed to the automatic transfer switch. Note the control
features that are provided and review their operation
before proceeding.

1 – Manual Operation Test

A detachable maintenance handle is provided on the frame
of the Transfer Switch for maintenance purposes only
Manual operation of the transfer switch should be
checked before it is energized (operated electrically).

left side of

transfer switch

.

Do not manually operate the transfer switch

until both power sources are disconnected:

open both circuit breakers.

1. After deenergizing both power sources, open the
enclosure door. Locate and remove the mainte­nance handle from the clips on the left side of the
transfer switch frame. Insert the handle into the hole
in the molded hub on the left side of the operator.
See Figures 1–3 and 1–4 and Table B.

2. Move the maintenance handle up or down as shown to
manually operate the transfer switch. It should operate
smoothly without any binding. If it does not, check for
shipping damage or construction debris.

Table B . Maintenance handle positions.

ATS Position Handle Indicators

Normal

Emergency

E

N

E

N

up

down

E=O

upper contacts o pen

N=C

lower contacts closed

E=C

upper contacts closed

N=O

lower contacts open

maintenance

handle

storage clips

Figure1-3.Maintenancehandle&storagelocation.

3. Return the transfer switch to the Normal position.
Observe that the window indicators (right side) show
the top shaft O (open) and the bottom shaft C (closed).

Note: If Normal and Emergency connections are

reversed this operation is also reversed.

4. Remove the maintenance handle and store it on the
frame (left side) in the clips provided.

Verify that the maintenance handle

has been removed before proceeding!

Now continue to 2–VoltageCheckson next page.

handle

UP closes the
Normal source
contacts (lower)

hub

DOWN closes the
Emergency source
contacts (upper)

frame

Figure 1-4. Maintenance handle operation and contact position indicators.

1 --- 3

Emergency
contacts

window

indicators

O is open
C is closed

Normal
contacts

contact position

indicators (right side)

INSTALLATION (continued)

Figure 1–5. St andard controls and indicators.

observe these lights

2–VoltageChecks

First check nameplate on transfer switch; rated voltage
mustbethesameasnormalandemergencylinevoltages.

Verify that the feeders have been

connected to the proper lugs.

Use extreme caution when using a meter
to measure voltages in the following
steps. Do not touch power terminals;
shock, burns, or death could result !

Performsteps 1 through 6 at the right. Observe the status
lights. See Figure 1–5.

● Black circle means light is on.
❍ White circle means light is off.

* If necessary, adjust voltage regulator on the generator
according to the manufacturer’s recommendations. The
Automatic Transfer Switch will respond only to the rated
voltage specified on the Transfer Switch nameplate.

Close the normal source circuit
breaker. The Normal Transfer
Switch Position and the Normal

1

Source Accepted lights should
come on.

Use an accurate voltmeter to
check phase to phase and
phase to neutral voltages pres-

2

entatthetransferswitchnormal
source terminals.

Close the emergency source
circuit breaker. (Start generator,
if necessary.) The Emergency

3

Source Accepted light should
come on.

Use an accurate voltmeter to
check phase to phase and
phase to neutral voltages pres-

4

ent at the transfer switch emer­gency source terminals.*

Useaphaserotationmeterto
check phase rotation of emer-

5

gency source; it must be the
same

as the normal source.

Source Accepted

Normal

Emergency

Source Accepted

Normal

Emergency

C

B

A

1 --- 4

Shut down the engine–genera­tor , if applicable. The Emergen-
cy Source Accepted light should
go off. Then put the starting

6

control selector switch (on the

Source Accepted

Normal

Emergency

generator set) in the automatic
position. Close enclosure door.

Now continue to 3 – Electrical Operation on next page.

pressthisbutton

INSTALLATION (continued)

observe these lights

Figure 1–6. Standard controls and indicators.

3 – Electrical Operation

This procedure will check the electrical opertion of the
Automatic Transfer Switch. See Figure 1–6.

Close the enclosure door first !

Transfer Test

Both normal and emergency sources must be available
and the emergency source generator (if used) must be
capable of being started in this procedure.

Performsteps 1 through 8 at the right. Observe the status
lights.

● Black circle means light is on.
❍ White circle means light is off.

NOTE: IfMotorLoadTransferfeature
is activated, then transfer may not occur
immediately after the respective time
delays. Transf er will only occur when
the phase relationship between sources
is correct.

This completes the Functional Test of the ASCO Series 300
Au tom atic Transfer Switch. Leave the engine–generator
starting control in the automatic position.

The normal source must be
available and the generator
must be ready to start.

1

Check that the Normal Source
Accepted light is on.

Press and hold the Transfer Test
button until the engine starts

2

and runs. This should happen
within 15 sec.

The Emergency Source

3

Accepted light should come on.

The transfer switch should
transfer to the Emergency
position. The Emergency

4

Transfer Switch Position light
should come on and the Normal
light should go off.

If the transfer to emergency
delay is used the transfer
should occurs after a time delay

5

(up to 5 minutes).
Forimmediatetransferpress
the Bypass Time Delay button.

The transfer switch should
transfer back to the Normal
position. The Normal Transfer

6

Switch Position light should
come on and the Emergency
light should go off.

If the retransfer to normal delay
is used the retransfer should
occur after a time delay

7

(up to 30 minutes).
Forimmediateretransferpress
the Bypass Time Delay button.

Source Accepted

Normal

Emergency

Trans fer

Tes t

Source Accepted

Normal

Emergency

Trans fer Switch

Position

Normal

Emergency

Bypass

Time Delay

Trans fer Switch

Position

Normal

Emergency

Bypass

Time Delay

1 --- 5

The unloaded running delay
keeps the generator running for
5 minutes (cool–down period).

8

Then the generator should stop
and the Emergency Source
Accepted light should go off.

Source Accepted

Normal

Emergency

SECTION 2 SEQUENCE OF OPERATION

Lights show position of transfer switch.

Transfer To Emergency

Thesequenceforloadtransferto
emergency source begins automati­cally when normal source voltage
falls below the preset dropout point
or when Transfer Test button is
pressed. An under voltage condition
on any phase of the normal source is
detected by the sensor.

When the norma l
source voltage fails or
the Transfer Test button
is pressed, the SE relay
de-energizes and relay
NR begins its timing
cycle (1 or 3 seconds,

momentary normal
source outage delay).

The NR relay is provided with a time delay on dropout to
override momentary outages and prevent nuisance starting
of the engine-driven generator. If the normal source voltage
returns above the sensor dropout setting before the time
delay expires, the NR relay timing cycle is reset to zero and
relay SE energizes.

If the normal source voltage does not return above the
sensor dropout setting before the time delay expires, the
NR relay de-energizes and signals the engine-driven
generator to start. At the same time, a voltage and
frequency sensor begins monitoring the emergency source.
The sensor will accept the emergency source only when

voltage and frequency reach preset pickup points.

both
Usually about ten seconds elapse from dropout of the NR
relay to acceptance by the sensor. This time span occurs
because the engine-driven generator must crank, start, and
run up to nominal pickup points. For this reason, if the
Transfer Test button is pressed it must be held for 15 seconds.
If the emergency sourceis availabl eimmediately, the sensor
may accept it as soon as NR relay drops out.

When the emergency source is accepted by the sensor,
relay ER begins its timing cycle (transfer to emergency
delay). ER relay is provided with an adjustable (0 to 5
minutes) time delay on pickup to delay transfer of the
load to the emergency source. For immediate transfer
press Bypass Time Delay button.

ER relay energizes, the TS coil is energized, the transfer
switch operates, and all switch contacts (mains, controls,
auxiliaries) reverse position. The transfer switch is now
supplying the load from the emergency source.

The tra nsfer switch will remain in the Emergency
position until the normal source i s restored. If the
Transfer Test button is used, the transfer switch will
remain on emergency until the retransfer to normal delay
times out.

Hold 15 sec.to
start the engine
generator and to
transfer the load
to emergency.

Press to cancel the
active exercise period
(stops engine now or
after cooldown) See
page 5–1.

Lights show the sources accepted.

Light for built–in

engine exercise timer:

➤ blinks rapidly when

button is held 5 sec.

while being set

➤ blinks slowly when

button is released (set)
and during 20 min.
exercise period.

➤ stays on after engine

stops (exerciser is

enabled for weekly

operation)

Seepage5–1

Hold 5 sec
20 min. engine exercise
period immediately (engine
starts) and weekly thereafter.

.toset

for complete

instructions

Figure 2–1. Membrane controls and indicator lights.

Retransfer to Normal

The sequence for load retransfer to the normal source
automatically begins when the voltage sensor detects
restoration of the normal source. The voltage level must
rise above the preset pickup point on all phases before
the sensor will accept the normal source.

Whenthenormalsourceisacceptedbythesensor,relay
SE begins its timing cycle (adjustable 1 sec. to 30 min.,
retransfer to normal delay). For immediate retransfer
press Bypass Time Delay button. SE relay is provided with
a time delay on pickup to prevent immediate load
retransfer to the normal source. The delay insures that
the normal source has stabilized before reconnection of
vital loads. If the normal source voltage falls below the
present dropout point before the time delay expires, the
timing cycle is reset to zero. If the emergency source fails
for more than 4 seconds during the timing cycle, ER relay
drops out and the load is immediately retransferred to
the normal source, if that source is acceptable.

SE relay energizes and ER relay is droppe d out. The TS
coil is energized, the transfer switch operates, and all
switch contacts (mains, controls, auxiliaries) reverse
position. The transfer switch is now supplying the load
from the normal source a gai n.

Upon retransfer to the normal source, NR relay beginsits
timing cycle (unloaded running delay [engine cooldown] ).
NRrelay is providedwith a 5minute time delay on pickup
to keep the engine running for a cool-down period.

NR relay energizes after the time delay and signals the
engine-driven generator to shut down. All circuits are
reset for any future normal source failure.

Activation of standard control features shown in Section 5
will alter the sequence of oper atio n and introduce
additional time delays during transfer operations.

2 --- 1

SECTION 3 TESTING & SERVICE

PREVENTIVE MAINTENANCE

Reasonable care in preventive maintenance will insure
high reliability and long life for the automatic transfer
switch.

Operate the switch at least once a month.Performthis
four step Electrical Operation Test. This is a test with
load transfer.

Transfer Switch Test

1. Press and hold the door-mounted Transfer Test
button until the engine starts and runs. This
should happen within 15 seconds.

2. The transfer switch will operate to the Emergency
position. If the Transfer To Emergency Del ay is
used, the transfer will occur after a time delay
(up to 5 minutes). For immediate transfer p ress
Bypass Time Delay button.

3. The Transfer Switch will operate back to the
Normal position after the R etrans fer To Nor mal
Delay (up to 30 minut es). For immediate
retransfer press Byp as s Time Delay button.

4. Unloaded Running (Engine Cooldown) Delay
allows engine to run unloaded for 5 minutes.

Clean and inspect the switch once a year. De-energize all
sources, then brush and vacuum away any excessive dust
accumulation. Remove the transfer switch barriers and
check contact condition. Replace contacts when pitted or
worn excessively. Reinstall the barriers carefully.

Maintain transfer switch lubrication.Thetransfer
switch has been properly lubricated, and under normal
operating conditions no further lubricating is required.
Renew factory lubrication if the switch is subjected to
severe dust or abnormal operating conditions.
Relubricate the operator if TS coil is replaced. Order
lubrication kit 75-100.

Replacement parts. Replacement parts are available in
kit form. When ordering parts provide the Serial No. and
Catalog No. from the t ransfer switch nameplate. Contact
your local ASCO Power Technologies sales office,
representative, or ASI. In the United States call
1–800–800–ASCO (2726), or in Canada call
1–888–234–ASCO (2726).

DISCONNECTING THE CONTROLLER

The harness disconnect plugs are furnished for repair
purposes only and should not have to be unplugged. If the
controller must be isolated, follow these steps carefully.

Disconnecting the Plugs

Do not unplug the controller until step

1a. or 1b. below is completed.

1. Observe the position of the transfer switch.
a. If the transfer switch is in the Normal position, place

standby engine starting control in the off position.
Then open the emergency source circuit breaker.

b. If the transfer switch is in the Emergency position,

open the normal source circuit breaker. Place the
engine starting control in the test or run position.

2. Separate the quick disconnect plugs by squeezing the

latches. Do not pull on the harness wires.

3. Label, remove, and tape the signal wires connected

to the engine start terminals on the transfer switch:
TB1 and TB3, or TB1 and TB2.

Reconnecting the Plugs

Do not reconnect the controller until step

1a. or 1b. and 2 below are completed.

1. Observe the position of the transfer switch.
a. If the transfer switch is in the Normal position, be

sure that the standby engine starting control is still
in the off positi on. The emergency source circuit
breaker still should be open.

b. If the transfer switch is in the Emergency position,

normal source circuit breaker still should be open.

2. Reconnect the signal wires connected to the

appropriate engine start terminals on the transfer
switch. See Section 1, Engine Starting Contacts.

3. The harness plugs and sockets are keyed. Carefully

align the plugs with the sockets and press straight in
until both latches click.

4. Restore the opposite source as follows:
a. If the transfer switch is in the Normal position,

place the standby engine starting control in the
automatic position. Then close the emergency
source circuit breaker.

b. If the transfer switch is in the Emergency position,

close the normal source circuit breaker. The load will
be automatically retransferred to the normal source
after the Retransfer to Norma l Delay. For immediate
retransfer, press Bypass Time Delay button. Place the
engine starting control in the automatic position.

3 --- 1

TESTING & SERVICE

PROBLEM

(continued)

MANUAL LOAD TRANSFER

This procedure will manually transfer the load if the
controller is disconnected.

Do not manually operate the transfer switch

until both power sources are disconnected:

open both circuit breakers.

TROUBLE-SHOOTING

Note the control features that are activated or furnished
on the switch and reviewtheir operation. Referto Section
5, Control Features.

Table 3-1. Trouble-Shooting Checks.

1OPERATION 2 GEN-SET 3VOLTAGE

Gen-Set does not start when
the Transfer Test button is
pressed and held for 15
seconds or when the normal
source fails.

T ransfer switch does not
transfer the load to
emergency source after the
gen-set starts.

T ransfer switch does not
transfer the load to normal
source when normal returns
or when Transfer Test button
is released.

Gen-Set does not stop after
load retransfer to the normal
source.

Hold the Transfer Test button
15sec.ortheoutagemustbe
long enough to allow for the 1
or 3 sec. Momentary Normal
Source Outage Delay plus
engine cranking and starting
time.

Wait for T ransfer to Emergen-
cy Delay (0 to 5 min.) to time
out. For immediate transfer,
press the Bypass Time Delay
button. If Motor Load Transfer
is active, wait for inphase con­dition (see below).

Wait for Retransfer to Normal
Delay (1 sec. to 30 min.) to
time out. For immediate re–
transfer, press Bypa ss Time
Delay button. If Motor Load
Transfer is active, wait for in­phase condition (see below).

Wait for the 5 minute
Unloaded Running Delay to
time out.

1. Open normal and emergency source circuit breakers.

2. Use the maintenance handle to manually operate

transfer switch to the opposite source. See page 1–3,
Manual Operation Test.

3. If the transfer switch is in the Emergency position

manually start the engine generator and then close
the emergency source circuit breaker.

Proceed with care!

The automatic transfer switch is energized.

CHECK IN NUMERICAL SEQUENCE

Starting control must be in
automatic position. Batteries
must be charged and
connected. Check wiring to
engine starting contacts.

Generator output circuit
breaker must be closed.
Generator frequency must be
at least 57 Hz.

—

Starting control must be in
automatic position.

Voltmeter should read at least
90% of nominal phase to
phase voltage between
transfer switch terminals EA
and EC (or EL1 and EL2 for 2
pole switches). *

* These are factory settings.

Voltmeter should read at least
90% of nominal phase to
phase voltage between
transfer switch terminals NB
and NC, NC and NA, and NA
and N B (or NL1 and NL2 for 2
pole switches).

—

—

Trouble-Shooting the Motor Load Transfer Feature (refer to page 5–4)

Use extreme caution when using a meter
to measure voltages in the following
steps. Do not touch power terminals;
shock, burns, or death could result !

1. Connect a voltmeter (set for twice system
phase–to–phase voltage) between Transfer Switch
terminals NA and EA.

2. Manually start generator. Voltmeter needle should
sweep back and forth at a regular rate between 0 and
about twice system voltage.

If the problem is isolated to circuits on the controlle r or the transfer switc h, call your loca l ASCO Power Technolog ies
sales office, representative, or ASI. In United States, call 1–800–800–2726 or e mail [e-mail] . In Canada,
call 1–888–234–2726. Furnishthe Serial No., Bill of Material (BOM) No ., & Catalog No . from transfer switch nameplate.

3. Press and hold

Transfer Test button. The load should
transfer to emergency source when meter needle is
near 0 volts. If transfer does not occur, Motor Load
Transfer feature is not operating.

4. Release the Transfer Test button. The load should
retransfer back to the normal source after the
Retransfer to Normal Delay,ifused. Theretransfer
should occur when the needle is near 0 volts. If
retransfer does not occur after the time delay, the
Motor L oad Transfer feature is not operating.

5. For immediate retransfer, press the Bypass Time
Delay button. Then disconnect the voltmeter.

3 --- 2

SECTION 4 ADJUSTMENTS

y

OverrideMomentary

TDE

S

—

T

TIMER

0minute

s

0to

5

——P

R

l

TIMER

30minutes

1secondto

——P

DESCRIPTIONLABELSSETTIN

G

S1DIP

PU/NP

ick

EmergencySource

equec

y

60/50

Vol

P

h

LOW/

Vol

Adj

)

LOW

/

H

I

Time Delay Adjustment

Standard time delays are set to customer specifications
(if none specified, standard factory settings are used).

Table4-1.TimeDelaySettings

DESCRIPTION LABELS

Override Momentar

Normal Source Outages

ransfer toEmergency

Override Momentary

Emergency S. Outages

etransfer toNorma

Unloaded Running

(Engine Cooldown)

FACTORY

SETTING

3seconds

TIMER 0 minutes 0to5

N/E

— 4seconds non-adjustable — — —

TIMER 30 minutes 1secondto

E/N

— 5 minutes non-adjustable — — —

(full ccw)

(full cw)

ADJUSTMENT

RANGE

1second Actuator 1 on

3seconds Actuator 1 off

minutes

30 minutes

Sensor Adjustments

Voltage and frequency sensor pickup and dropout points
are set to customer specifications (if none specified,
standard factory settings are used). To change a setting,
follow procedure on page 4–2. Use Tables 4-2 and 4–3for
settings and corresponding DIP switch actuators.

To change a setting, follow procedure on page 4-2. Use
Table 4-1 as a guide to time delay values and their corre­sponding adjustment DIP switch or potentiometer.

S3 DIP

SWITCH

1

1

ADJUSTMENT

POTENTIOMETER

2

1

Any change in these settings may affect the
normal operation of the automatic transfer
switch. Thischange could allow the load circuits
to remain connected to a low voltage source.

Table 4-2. Voltage and Frequency Settings. (

Normal Source Voltage

DO/N Dropout

EmergencySource

Voltage

Emergency Source

Frequency

tage

ases 3, 1 3/1 3

–– Pickup 90 % non-adjustable
–– Dropout 75 % non-adjustable
–– Pickup 95 % non-adjustable
–– Dropout 85 % non-adjustable

60/50

Hz

60/50Hz 60Hz

* If dropout voltage is set to 90%, the pickup voltage must be set to 95%.

FACT. S ET ADJ RANGE

up 90 %

85 %

Shaded DIP switches are standard factory settings).

%ofnominal

95 % * Actuator 3 off

90 % Actuator 3 on

90 % *

85 %

80 %

70 %

60 Hz Actuator 4 off

50 Hz Actuator 4 on

3phase Actuator 6 off

1phase Actuator 6 on

Actuator 1 off
Actuator 2 off

Actuator 1 on
Actuator 2 off

Actuator 1 off
Actuator 2 on

Actuator 1 on
Actuator 2 on

––

––

S1 DIP

SWITCH

3

3

21

21

21

21

4

4

6

6

Table 4-3. Transformer Voltage Adjust.

(Low setting shifts all voltage settings down 4.2%; for example, 240 V to 230 V, or 480 V to 460 V)

DESCRIPTION LABELS FACTORY SET T ING ADJUSTMENT S3 DIP SWITCH

tage

ust(4.2%

HI

4 --- 1

LOW Actuator 2 off

HI Actuator 2 on

2

2

ADJUSTMENTS

(continued)

Do not make any setting changes

while the controller is energized.

How to Change a Setting

1. Prevent the transferswitch from operating by discon­necting one source first, then the other, as follows:

a. If the transfer switch is in the Normal position,

open the emergency source circuit breaker. Turn
the engine starting control to off. Then open the
normal source circuit breaker.

b. If the transfer switch is in the Emergency

position, open the normal source circuit breaker.
Turn engine starting control to test or run.Then
open the emergency source circuit breaker.

2. Disconnect both harness plugs from controller by
squeezing the latches. Do not pull on the wires.

3. Remove cover from the controller by releasing latch
on right side with your thumb. See Figure 4-1.

4. Locate the appropriateadjustment potentiometeror
DIP switch for the setting that you want to change.
Refer to Table 4-1 and Table 4–2 on page 4-1 and
Figure 4-2, Figure 4–3, Figure 4–4 on page 4–2.

5. Use a small screwdriver to turn the potentiometer
clockwise to increase the time delay or counterclock­wise to decrease it. See Figure 4-3.

6. Use a ball-point pen (or similar pointed tool) to slide
the switch actuators left or right so they match the i l­lustration next to the setting (left = off, right = on).
Recheck the setting. See Figure 4-4.

7. Install the cover on the controller by hooking it on
the left side and latching the right side.

8. Reconnect both harness plugs to the controller by
aligning and pressing straight in until lat ches click.

cover

hook on
left side

Figure 4-1. Controller cover latch.

harness

plugs

S3 DIP

switch

S1 DIP

switch

Figure 4-2. Location of potentiometers.

clockwise to

increase

P1 or P2

potentiometer

counterclockwise

to decrease

S2 DIP

switch

thumb
latch

9volt

alkaline

battery

J5

battery
on/off
jumper

P1
retransfer
to normal

time delay

P2

transfer to

emergency

time delay

Close the enclosure door.

9. Close the enclosure door, then restore both sources:

a. If the transfer switch is i n the Normal position

first close the normal source circuit breaker,
then close the emergency source circuit breaker.

b. If the transfer switch is in the Emergency

position, close the normal source circuit breaker.
The load will be automatically retransferred to
the normal source. Then close the emergency
source circuit breaker.

10. Turn the engine starting control to automatic.

Figure 4-3. Changing time delay potentiometers.

DIP

switches

SW1
SW2
SW3

actuator

(8 on each DIP switch)

onoff

Figure 4-4. Setting DIP switch actuators.

4 --- 2

SECTION 5 CONTROL FEATURES – ENGINE EXERCISERS

These timers periodically exercise the emergency engine-generator plant. They can be set to exercise with or without
loadtransfer, or they can be completely disabled. The engine-generator shouldbe exercised under loadonce a week for a
minimum time period of 20 minutes, or follow the recommendations of the engine-generator set manufacturer. Refer to
page 4–2 for location of DIP switches, battery (provided), and jumper block in the controller.

BUILT–IN ENGINE EXERCISER

The engine exerciser included in ASCO Series 300
Automatic Transfer Switches provides a once a week
20–minute exercise period. It occurs immediately
the Set Engine Exerciser push button is pressed (and
held

for at least 5 seconds), and then at the same time
weekly thereafter. A 9 volt alkaline battery (DuracellR
MN1604, EverreadyR 522, or PanasonicR 6AM6) is
furnished and installed in the controller to maintain the
setting. The battery jumper block must be shifted to
ON position

. See Figure 4–2 on page 4–2.

when

the

FUNCTION

Std. Timer

Enabled

Std. Timer

Disabled

Exercise

without

Load

Exercise

with Load

Shaded DIP switches are standard factory settings.

DIP Switch Settings

S1 DIP

SWITCH

Actuator

7on

Actuator

7off

Actuator

8off

Actuator

8on

7

7

8

8

Actuator

5on

Actuator

5on

S2 DIP

SWITCH

5

5

Fill in day and time set. Week Day ______ Time _______.

Press to cancel an active exercise
period (stops generator).

If Exercise with Load is set, retransfers load to
Normal, then stops generator after min. cooldown.

status light

Press and hold for 5 sec
blinks rapidly to set exercise period immediately
and every week hereafter (generator starts).

. or until status light

If Exerciser with L oad is set,
transfers load to Emergency.

Figure 5-1. Operator panel pushbuttons and light.

Select below either Exercise without Load or Exercise with Load accordingto the setting of DIP switch S1, actuator 8. The
load transfers from the Normal source to Emergency source (generator) and back again if Exercise with Load is selected.

Exercise without Load, DIP Switch S1, Actuator 8 off

8

How to Set Built–In Timer

Step Function Explanation

Push Button Status Light

Set Engine

1

Exercise r

hold

5sec.

2 release

press Bypass

3

Time Delay

blinks rapidly

●❍●❍●❍

blinks slowly

●❍❍●❍❍

set exercise period

exercise period now active Generator starts and runs.

Exercise the generator now and

every week at this time hereafter.

● stays on cancel active exercise period Generator stops.

4 — ● stays on generator off Exerciser enabled; repeats every 7 days.

Exercise with Load, DIP Switch S1, Actuator 8 on

8

How to Set Built–In Timer

Step Function Explanation

Push Button Status Light

Set Engine

1

Exercise r

hold

5sec.

2 release

press Bypass

3

Time Delay

blinks rapidly

●❍●❍●❍

blinks slowly

●❍❍●❍❍

blinks slowly

●❍❍●❍❍

set exercise period

exercise period now active

cancel active exercise period

Exercise the generator now and

every week at this time hereafter.

Generator starts and runs;

the load transfers to Emergency.

The load retransfers to Normal; then

generator runs for 5 minute cooldown

( light blinks slowly during cooldown ).

4 — ● stays on generator off Exerciser enabled; repeats every 7 days.

NOTE:EverytimeSET ENGINE EXERCISER push button is pressed (held 5 seconds) the exercise period is changed.

5 --- 1

2–line
display

3 buttons

CONTROL FEATURES (continued)

Optional Accessory 11BG – SOURCE AVAILABILITY SIGNAL

& PROGRAMMABLE ENGINE EXERCISER MODULE

connections
for source
availability
signal contacts

Figure 5–2. Accessory 11BG module (mounted behind operator interface and connected to the controller)

includes source availability signal contacts and a programmable engine exerciser.

Source Availability Signal Contacts

ThemoduleprovidesoneFormCcontacteachforthe
normal and emergency sources signal the acceptability of
the source as se nsed by the controller. The signal contacts
operate in conjunction with the Source Accepted lights on
the operator interface. Field wiring terminals are
provided as shown in Figure 5–3 and the wiring diagram.

SOURCE

AVAILABILITY SIGNALS

2 AMPS @ 30 VDC, re sistive

0.5 AMP @ 125 VAC, resistive
contacts shown de–energized

Contact ratings:

2 amps @ 30 Vdc, 0.5 amp. @ 125 Vac resistive

Figure 5–3. Source availability signal contacts.

ProgrammableEngineExerciser

Themoduleincludesaprogrammableengineexerciser
that provides for weekly or biweekly operation. This
optional exercise timer may have to be turned on
(enabled) by setting the S1 DIP switch actuator 7 to off,
and S2 DIP switch actuator 5 to off. A backup battery

in
the controller (see page 4–2 and page 5–3) must be turned
on to maintainthe settings and to allow programming with
the normal and emergency power turned off (page 5–1).

Theprogrammableengineexerciserincorporatesa7day
or 14 day time base. Proper controller settings must be
made to determine whether or not the test will be done
with or without load transfer (S1 DIP switch actuator 8).

DIP Switch Settings in the Controller

(see page 4–2)

FUNCTION

Opt. Timer

Enabled

Opt. Timer

Disabled

Exercise

without

Load

Exercise

with

Load

SWITCH

Actuator

7off

Actuator

7off

Actuator

8off

Actuator

8on

S1 DIP

7

7

8

8

S2 DIP

SWITCH

Actuator

5off

Actuator

5on

5

5

Seenextpageforinstructionsonsettingthetimer.

Shaded DIP switches are standard factory settings.

5 --- 2

CONTROL FEATURES (continued)

How to Set Optional Programmable Engine Exerciser (part of Acc. 11BG module)

For example, if the user wants the exerciser to run every
other Saturday a t 3 PM, the proper configuration would

Hazardous voltage capable of causing shock,
burns, or death is used in this transfer switch.

Deenergize both Normal & Emergency power

sources before programming the exerciser.

be:

“Alt Sat @ 15:00”

NOTE: When choosing bi–weekly operation, the
exerciser will always run on the week designated “(1)” on
thedatedisplay.

Navigating the Menu

Use the UP and DOWN arrow
keys to move through the displays .

Changing the Parameters

Use the UP and DOWN arrow
keys to move though the displays
to the parameter to be changed.
Push the ENTER key to start the
editing process. The first
parameter will flash. Use the UP
and DOWN arrow keys to adjust
the parameter to the desired
value and press the ENTER key
to save the value. The next
parameter will now flash. Repeat
the process until each parameter
is properly configured.

Fast/Slow Ad ju st

Daylight Saving

Time Adjust

Date

Time

Run TIme

Start TIme

Engine Exerciser

Engine Exerciser Display

TheEngineExerciserDisplay
shows the status of the engine
exerciser. When the unit is shipped from the factory the
programmable engine exerciser is “Disabled” and must be
set to “Enabled” by the customer. When the engine
exerciser is running, this display will count down the
remaining time until the end of the exercise period.

Start Time Display

The Start Time Display shows the engine exerciser start
time. There are four parameters that determine the start
time:

weekly (”Every”) or bi–weekly (”Alt”) operation

day of week (”Sun” through “Sat”)

start hour (0 through 23)

start minutes (0 through 59)

Fill in your settings for future reference

Run Time Display

The Run Time Display shows the run time for the engine
exerciser. The default setting from the factory is 30
minutes.

Time Display

The Time Display shows the present system time. The
format is “hours:minutes:seconds”.

NOTE: During total power outages, power to the
accessory is maintained by a battery in the Controller (see
page 4–2). Be sure that the 9–volt alkaline battery is fresh
and enabled (jumperin ON position) so that the time and
date settings are not lost.

Date Display

The Date Display shows the present system date. The
format is “day of week (week) month/day of month/year”.

NOTE: Week is either week 1 or week 2. This is used in
conjunction with the bi–weekly timer.

Daylight Savings Time Adjust Display

This display shows whether the automatic daylight saving
time adjustment is active. The factory default is “NO”. If
enabled, the unit will automatically adjust for daylight
saving time at 2 AM on the first Sunday of April and the
last Sunday of October.

Fast / Slow Adjust Display

This display shows the automatic fast/slow adjustment
value.Thefactorydefaultis0.Thisfeaturecanbeusedto
trim a clock that runs fast or slow. For example, if your
clock runs 10 seconds slow per week, change the fast/slow
adjust value to “+10” and the unit will automatically add
10 seconds to the clock every week.

NOTE: Adjustments are made Sunday morning at 2 AM.
If you want your exerciser period to start at 2 AM on
Sunday, you cannot use this feature and the adjustment
must be set to 0.

Weekly or Bi–weekly Day of Week Start Time Run Time

Every = weekly
Alt = bi–weekly

Date exerciser was set ______________________________________

Sun through Sat

5 --- 3

0–23hour

0–59minute

0–23hour

0–59minute

30 min. is default setting

CONTROL FEATURES (continued)

INPHASE MONITOR

FOR MOTOR LOAD TRANSFER

Inphase monitoring logic controls transfer and retransfer
of motor loads, so that inrush currents do not exceed
normal starting currents. It avoids nuisance tripping of
circuit breakers and mechanical damage to motor
couplings.

The Motor Load Transfer feature is built into the
controller. DIP switch S1 (actuator 5) activates this
feature: right = ON, left = OFF.

FUNCTION S1 DIP SWITCH

enable Actuator 5 on

disable Actuator 5 off

Shaded DIP switches are standard factory settings.

Note

If the Motor Load Transfer feature is enabled,
it will be activated following

the Load
Disconnect Feature Delay Before Transfer
delay.

5

5

LOAD DISCONNECT FEATURE

Connect external circuits to the terminals indicated on the
Wiring Diagram provided with the ATS.

The double throw (Form C) contact is rated for 28 VDC or
120 VAC (5 amps resistive). The contactoperates prior to
a selectable 0, 3, 10, or 20 second delay before transfer of
the Automatic Transfer Switch. The contact resets either
immediately following transfer or after the same

delay as

set for pre–signal before transfer.

Time delay between the load disconnect control signal
and initiation of transfer is set on the controller with DIP
switch S2 (actuators 6, 7, 8) as shown below:

Delay Before Transfer

LD TDBT S2 DIP SWITCH

0 (disable)

3seconds

10 seconds

20 seconds

Actuator 7 on
Actuator 8 on

Actuator 7 on
Actuator 8 off

Actuator 7 off
Actuator 8 on

Actuator 7 off
Actuator 8 off

87

87

87

87

Shaded DIP switches are standard factory settings.

Delay After Transfer*

LD TDAT S2 DIP SWITCH

enable Actuator 6 on

disable Actuator 6 off

6

6

*Enabling the Delay After Transfer will cause the control
signal to reset after the same delay

as set for the Delay

Before Transfer.

REMOTE CONTROL FEATURES

These remote control features require a customer–supplied normally closed contact suitable for a 5 V dc low energy
circuit. Refer to the Wiring Diagram provided with the ATS. Activate appropriate DIP switch S2 actuators below.

Remote Test (terminals CP6–7)

RTSW S2 DIP SWITCH

disable Actuator 3 on

enable Actuator 3 off

3

3

Remote Transfer to Emergency (CP8–9)

RT /E S2 DIP SWITCH

disable Actuator 2 on

enable Actuator 2 off

2

2

Bypass Transfer Time Delay (CP12–13)

TD E/N BYP. S2 DIP SWITCH

disable Actuator 1 on

enable Actuator 1 off

Inhibit Transfer to Emergency (CP10–11)

N/E INHIB. S2 DIP SWITCH

1

1

disable Actuator 4 on

enable Actuator 4 off

5 --- 4

4

4

CONTROL FEATURES (continued)

OPTIONAL STRIP HEATER (Accessory 44)

Accessory 44 Strip Heater is designed to keep ambient
temperatures within the Automatic Transfer Switch
enclosure at acceptable levels. This accessory consists of a
mounting bracket with strip heater, thermostat, and
terminal block. A transformer with fuses is included when
the power for the assembly is derived from voltages above
120 V ac. The 120 V ac customer powered assembly does
not include a transformer. This optional accessory is
available factory installed or in kit form.

Turn the thermostat’s dial to required setting as shown.

thermostat

dial

turn counterclockwise

to lower temperature

turn clockwise

to raise temperature

AVAILABLE KITS FROM ASCO

Controls

Description Accessory Kit

ProgrammableEngineExerciser

& Source Availability Contacts

Serial Communication Module 72A K601110

11BG K629830

Figure 5–4. Thermostat.

Strip Heater – Accessory 44

Description Accessory Kit

120 volt

customer supplied voltage

(without transformer)

208 – 480 volt

ATS derived voltage

(with transformer)

380 volt

ATS derived voltage

(with transformer)

550 – 600 volt

ATS derived voltage

(with transformer)

44A K613127–001

44G K613127–002

44G K613127

44G K613127–003

5 --- 5

A

G

INDEX

strip heater, 5–5

accessories, 5–2, 5–5

auxiliary circuits, 1–2

B

battery, 4–2, 5–1

buttons, push, 3–1

bypass time delay, 1–5, 2–1, 3–1

C

cable

lugs, 1–1
preparation, 1–1

catalog number, inside cover

cleaning, 3–1

connections

engine control contact, 1–2
line, 1–1

contact position indicators, 1–3

contacts

auxiliary, 1–2
engine control, 1–2
main, 1–3, 3–1
source availability signal, 5–2

control features, 5–1

load disconnect, 5–4
motor load transfer, 5–4
plant exerciser, 5–1, 5–2, 5–3

controller, 4–1, 4–2

codes, cover
cover removal, 4–2
disconnecting, 3–1
time delay potentiometers, 4–2

D

DIP Switches, 4–1, 4–2, 5–1, 5–2, 5–4

E

electrical operation, 1–5

engine exerciser, 5–1, 5–2, 5–3

engine starting contacts, 1–2

F

features, see control features

frequency, pi ckup and dropout

settings, 4–1

functional test, 1–3, 1–4, 1–5

ground, controller, 1–1

H

handle, maintenance, 1–3

warning, 1–3

harness, 1–2

disconnect plugs, 3–1

HELP

800–800–2726 (ASCO)
[e-mail]

I

inphase monitor, 5–4

inspection, 3–1

installation, 1–1

L

labels,

engine starting contacts, 1–2
inputs / outputs, 1–2
rating, cover

lights, 1–4, 5–1

load disconnect feature, 5–4

lubrication, 3–1

M

maintenance, preventive, 3–1

manual load transfer, 3–2

warning, 3–2

manual operation, 1–3

warning, 1–3

motorloadtransferfeature,5–4

N

nameplate, cover

O

operation

electrical, 1–5
manual, 1–3

illustration of, 1–3
warning, 1–3

sequence of, 2–1

optional accessories

programmableengineexerciser

& source availability signal
contacts, 5–2, 5–3

serial communication module, 5–5

P

parts, 3–1

problem, 3–2

programmable engine exerciser, 5–2,

5–3

R

rating label, cover

remote control features, 5–4

bypass transfer time delay, 5–4
inhibit transfer to emergency, 5–4
remote test, 5–4
remote transfer to emergency, 5–4

replacement parts, 3–1

S

service, call 800–800–2726 (ASCO)

set engine exerciser, 5–1, 5–2, 5–3

settings

changing, 4–1
factory, 4–1
frequency, 4–1
phase, 4–1
time delay, 4–1
voltage, 4–1

source accepted lights, 1–4, 1–5

T

terminal block, 1–2

test, functional, 1–3, 1–4, 1–5

time delay

adjustment, 4–1
gen–set cooldown, 4–1
how to change, 4–2
override momentary outages, 4–1
transfer to emergency, 4–1
transfer to normal, 4–1

timer (plant exerciser), how to set,

5–1, 5–2, 5–3

transfer switch position lights, 1–4,

1–5

transfer test, 1–5, 3–1

trouble–shooting, 3–2

V

voltage, phase, 4–1

voltage, pickup and dropout settings,

4–1

Printed in U.S.A.

Copyright --- ASCO Power Technologies, L.P. 2007