Mueller-Electric-ARM-120-AFEP

The

ARM Series

Alternating Relay is a

microprocessor-based  

controller

designed for use in dual load installations to assure  

equal run time on each loadꢃ LED indicators show the status of  

the unit’s five intrinsically safe control switch inputs% one alarm%  

and two load outputsꢃ H-O-A switches% a lead select switch% and a  

testꢂclear button are provided for manual controlꢃ The ARM Series  

reduces the number of components required for this application  

by combining many functions into one unitꢃ  

Process  

Control  

Equipment for  

Hazardous  

Locations  

7M26  

UL913  

INCLUDES  

INTRINSICALLY  

SAFE INPUTS  

TWO PUMP SEQUENCING:

Evenly distributes run time by  

automatically alternating lead and lag load designations when the off  

control switch input opensꢃ  

UL913 INTRINSICALLY SAFE:

Control switch inputs are low voltageꢂ  

low current and are electronically isolated from the control voltage  

and load alarm contactsꢃ  

Integrated Duplex Controller  

SOSO Operation  

(Sequence-on, Simultaneous-off)  

H-O-A Switches: Hand-Off-Automatic switches allow for manual  

operationꢃ  

LEAD SELECT SWITCH:

Disables the automatic sequencing function  

and allows loads to be locked into the 2-1 or 1-2 sequenceꢃ  

CONTROL SWITCH FAULT DETECTION:

Unit detects open and  

shorted control switch failuresꢃ  

SPECIFICATIONS  

CONTROL VOLTAGE

 

24 or 120 VAC

 

10ꢀ% ꢁ0ꢂ60 Hz  

TEST/CLEAR SWITCH:

Verifies function and resets the control  

CONTROL SWITCH

 

Open Circuit

 

ꢁ VDC  

switch fault detection algorithmꢃ  

Voltage  

Short Circuit

 

0ꢃ1mA  

Voltage  

ALARM OUTPUT:

Alarm contacts close when a control switch  

fails or the system’s capacity is exceededꢃ  

INRUSH CURRENT DELAY:

Reduces line sags by preventing  

both loads from energizing simultaneousl

y

ꢃ  

POWER REQUIRED

 

4 VA Maximum  

DUTY CYCLE  

RESPONSE  

Continuous  

VERSATILE MOUNTING:

Two (2) mounting configurations are  

availableꢃ The standard surface mount has top access to controls  

and indicators and is intended for back panel mountingꢃ The panel  

mount option is intended for front panel or door cutout access to  

controls and indicatorsꢃ  

Power Up  

Inrush Current

 

ꢁ SECꢃ

 

ꢁꢀ  

3 SECꢃ

 

ꢁꢀ  

CONTACT  

RATING  

(3) SPST-NꢃOꢃ 10 Amp Resistive% 1ꢂ4 hp% 278 VA  

Inductive @ 120 VAC  

SPECIAL CONTROLS: ARM-2003

and

ARM-2010

–Standard  

operation without the H-O-A switches

ARM-2011

–Standard  

operation without the Control Switch Failure featureꢃ  

LED INDICATORS  

Designation  

LevelꢂAlarm  

Lag  

Lead  

Off  

Color  

Red  

Green  

Green  

Green  

Green  

State  

ON  

ON  

ON  

ON  

Condition  

csꢁ Closed  

cs4 Closed  

cs3 Closed  

cs2 Closed  

cs1 Auxꢃꢂcs2  

Closed  

Load ON  

Load ON  

Failure  

OpenꢂClosed  

ORDERING INFORMATION  

Auxꢃ Off  

ON  

MODEL  

NUMBER  

CONTROL  

VOLTAGE  

Load 1  

Load 2  

Ctrlꢃ Switch  

Green  

Green  

Red  

ON  

ON  

ON  

MOUNTING  

COMMENTS  

ARM-XXX-AFE*  

ARM-XXX-AFEP* 24

 

or 120 VAC  

24 or 120 VAC  

Surface  

Panel  

Standard  

Standard  

ARM-2003  

ARM-2010  

ARM-2011  

120 VAC  

120 VAC  

120 VAC  

Surface  

Special: wꢂo  

H-O-A switches  

Special: wꢂo  

H-O-A switches  

Special: wꢂo  

Control switch  

failure feature  

LIFE EXPECTANCY

 

Mechanical  

20 Million Operations  

7ꢁ%000 @ Rated Load  

Electrical  

Panel  

TEMPERATURE  

RATING  

Operate  

Storage  

-4° to 131°F (-20° to +ꢁꢁ°C)  

-40° to 18ꢁ°F (-40° to +8ꢁ°C)  

Surface  

TERMINATIONS  

(12) #8-32 Screw Terminals  

WEIGHT

16 ozꢃ  

*Replace XXX with desire control voltage (24% 120)  

The ARM Series is UL Listed under UL File Number E1ꢁ1ꢁ78ꢃ  

196  

Diversified Electronics  

800.727.5646 atcdiversified.com  

DIMENSIONS

(INCHES)  

OPERATION  

FOUR CONTROL SWITCHING:

Do not remove factory-installed  

jumper between terminals 2 and 3ꢃ The control switches connected  

to terminals 3 through 6 are labeled OFF (CS2)% LEAD (CS3)% LAG  

(CS4) and ALARM (CSꢁ)ꢃ Under normal operation the lead load  

energizes when the off and lead control switches close in orde

r

ꢃ

T

he  

lag load energizes when the lag closes and the alarm load energizes  

when the alarm switch closesꢃ When all four switches reopen in the  

proper order all outputs are de-energized and the leadꢂlag output  

designations reverseꢃ  

FIVE CONTROL SWITCHING:

Remove factory installed jumper  

between terminals 2 and 3ꢃ After the jumper has been removed% the  

additional control switch is connected to terminal 2ꢃ The extra switch  

functions as an AUXILIARY OFF (CS1) switchꢃ It is used to prevent  

loads from running continuously if the primary OFF (CS2) switch  

fails to open properl

y

ꢃ  

*Panel Mount Cutout  

FAULT DETECTION ALGORITHM:

If any of the control switches  

open or close out of order% the alarm output energizes and a fault  

detection algorithm is used to identify the faulty switchꢃ The faulty  

switch is then ignored and the OF

F

%

L

EAD% and LAG control switch  

designations are altered to maintain safe operationꢃ  

*Greenlee punch #60071 or equivalent  

WIRING  

CONTROL DRAWING 190  

1ꢃ To

 

maintain intrinsic safet

y

%

c

onnect the Controller’s Earth Ground Terminal 8 to the earth ground of the AC Power Supply feede

r

ꢃ  

The resistance between the Controller’s Earth Ground Terminal and Earth Ground shall be less than 1 ohmꢃ  

2ꢃ Maximum

 

distance between Controller and switch contact is 1000 feetꢃ  

3ꢃ All

 

intrinsically safe wiring shall be separated from non-intrinsically safe wiringꢃ Refer to article ꢁ04 of the National Electrical Code  

ANSIꢂNFPA 70 on procedures for intrinsically safe wiringꢃ  

4ꢃ Switch

 

contact shall be any non-energy storing or generating mechanical switch type device containing no capacitance or inductanceꢃ  

ꢁꢃ Connections

 

to terminals ꢁ% 6% 9% 10% 11% and 12 are optionalꢃ If the Auxꢃ Off switch is omitted% terminals 2 & 3 must be jumperedꢃ  

197  

Diversified Electronics  

800.727.5646 atcdiversified.com