ZIMCO ROBINSON RS74A User manual

Models: RS74A & RS74M
Flow Line Pressure Switch
Installation & Operation Manual
Hazardous Location Pressure Switch
11141 15 Street NE, Calgary, AB, T3K 0Z5, Canada
Phone: [phone] Email: [email protected] Website: www.zimco.ca

2
2 Quick Installation
2.1 Inspect all threaded connections and ensure
they are all damage free.
2.2 Prepare Process Connection (Trim Bushing)
Threads by applying PTFE (Teflon) tape or
sealant.
2.3 Use knurled pipe wrench area on Process
Connection to thread into place.
2.4 Inspect threads in the Electrical Conduit Port
(1/2” FNPT) as well as the electrical cable
assembly fitting to ensure cleanliness and
free of damage.
2.5 Feed wire leads through the Electrical
Conduit Port and tighten the electrical
cable assembly fitting. Refer to the wiring
diagram on next page to attach wires to
micro switch.
1 Safety
1.1 Power supply must be disconnected before installation, calibration and maintenance.
1.2 Keep all components dry and free from damage.
1.3 Review applicable standards to ensure Robinson Pressure Switch is the correct switch for
the application.
1.4 Personnel must wear appropriate safety approved apparel for working environment.
1.5 Only qualified personnel should install the Robinson Pressure Switch and accessories.
1.6 A qualified electrician is required to inspect wiring installation prior to applying electricity.
1.7 Ensure Enclosure cover is in place prior to applying electricity.
Electrical
Conduit
Port 1/2”
FNPT
Knurled
Pipe/Strap
Wrench
Area
Process
Connection
(Trim Bushing)
Adjustment
Collar
2” MNPT
Connection
Figure 1
ZIMCO INSTRUMENTATION INC.
11141 15 Street NE, Calgary, AB, T3K 0Z5, Canada
Phone: [phone] Email: [email protected] Website: www.zimco.ca

3
Manual Reset Automatic Reset
Normally
Closed
Ground
Normally
Open
Normally
Closed
Ground
Normally
Open
Common Common
Single Pole Double Throw
15A—125, 250 or 480 VAC
1/4 HP—125 VAC, 1/2 HP– 250 VAC
1/2A—125 VDC, 1/4A—250 VDC
Single Pole Double Throw
15A—125, 250 or 480 VAC, 2A—600 VAC
1/8 HP—125 VAC, 1/4 HP—250 VAC
1/2A—125VDC, 1/4A—250 VDC
Notes Regarding Wiring
Ensure wire insulation is not damaged
Connect Wires Firmly to micro switch terminals
(torque to 4 inch lbs.)
Wiring must meet or exceed circuitry requirements
3.1 Use 3/16“ hex key to loosen the Enclosure
Cover/Security feature.
3.2 Use a spanner wrench (1/4” pin, 2-4 3/4”
span) to break loose the Enclosure Cover and
Complete removal by hand.
3.3 Connect wires to micro switch as required.
3.4 Thread 1/2” MNPT electrical cord Union into
the Electrical Port located on the side of the
electrical enclosure housing, 5+ Turns
3.5 Thread Enclosure Cover back onto the
Electrical Enclosure and ensure it is properly
seated prior to applying electricity.
3 Wiring
Electrical
Enclosure
Cover
3/16” cap screw
locks cover in place
and fastens car seal
locking feature
1/2”FNPT
Electrical
Conduit Port
Figure 2
Figure 3 Figure 4
ZIMCO INSTRUMENTATION INC.
11141 15 Street NE, Calgary, AB, T3K 0Z5, Canada
Phone: [phone] Email: [email protected] Website: www.zimco.ca

4
Cap Screw
Location
Calibration Screw
Not to be used for general set point
adjustment
The Calibration Screw is used for:
A) Initial factory calibration and after
Micro Switch replacement.
B) To reach pressure settings at up-
per or lower extremes.
Call factory for detailed instructions.
4 Setting Trip Pressure
Note: pressure gauge and pressure source are needed to set and verify settings
4.1 Cut off Zip Tie (or Car Seal)
4.1 Loosen Cap Screw (3/16” hex hey) Located on upper part of Adjustment Collar
Loosen Set Screw to Allow turning of Pressure Adjusting Collar
4.2 Pressure Setting
Turn Collar Clockwise to Increase Pressure Setting
Turn Collar Counter Clockwise to Decrease Pressure Setting
4.3 Tighten Cap Screw
Tighten Cap Screw to lock Pressure Adjusting Collar in position.
Adjustment Collar
5 Notes Regarding Calibration
5.1 Calibration is not required after re-setting & verifying trip pressure.
5.2 Calibration (micro switch gap setting) is required when the Micro Switch has been
replaced or if disassembly and re-assembly has occurred.
Refer to Repair Manual for calibration instructions at www.robinsoncontrols.com
Figure 5
ZIMCO INSTRUMENTATION INC.
11141 15 Street NE, Calgary, AB, T3K 0Z5, Canada
Phone: [phone] Email: [email protected] Website: www.zimco.ca

5
RS74A
Auto Reset
6 Specifications
Models: RS74A and RS74M
6.1 Pressure Range
50 to 1500 psi (345 to 10,340 kPA)
6.2 Max Safety Pressure
5000psi (34,473 kPA), all models.
6.3 Temperature Range
Auto Reset
Process temperature –45°C to 140°C
Ambient Temperature -40°C to 60°C
Manual Reset
Process temperature –45°C to 120°C
Ambient Temperature -40°C to 40°C
6.5 Certification Markings
Class I, Division 1, Groups B, C and D; Type 4
Ex d IIB+H2; IP54
Zone 1 AEx d IIB+H2; IP54
Tamb -40˚C to +60˚C; T4
Use Supply Wires Suitable For 96˚C
6.6 Process Connection; NACE MR0175-2003
2” MNPT Threaded Connection
SA350 LF2 Class 1, Zinc Plated
Diaphragm Inconel 718
Retaining Ring 316 SS
CRN: 0F10666.2
6.7 Input Ratings (model dependent)
RS74M
Manual Reset
Figure 6
Manual Reset Auto Reset
Single Pole Double Throw
15A—125, 250 or 480 VAC
1/4 HP—125 VAC, 1/2 HP– 250 VAC
1/2A—125 VDC, 1/4A—250 VDC
Single Pole Double Throw
15A—125, 250 or 480 VAC, 2A—600 VAC
1/8 HP—125 VAC, 1/4 HP—250 VAC
1/2A—125VDC, 1/4A—250 VDC
IMPORTANT INFORMATION -Process Temperature Testing
Pressure Switches with the minimum Class 1 Div 1 name plate markings do not meet CSA C22.2 No
E60079-0:2007 which requires a maximum process temperature to be applied for explosion proof test-
ing.
All Robinson Pressure Switches in addition to meeting the minimum Class 1 Div 1 have also been tem-
perature tested to CSA C2.2 No E60079-0:2007 and are legally allowed to have the additional markings
of Ex d IIB+H2; IP54 Zone 1 AEx d IIB+H2; IP54 Tamb -40˚C to +60˚C; T4
ZIMCO INSTRUMENTATION INC.
11141 15 Street NE, Calgary, AB, T3K 0Z5, Canada
Phone: [phone] Email: [email protected] Website: www.zimco.ca

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F C
Dual Seal Certification Meets ANSI/ISA-12.27.01-2003 dual seal certification
Annunciation Check Valve
(a dual seal feature)
Visually indicates a primary seal failure.
Unlike open holes found on competitive models the Robinson check
valve prevents moisture and debris from contaminating internal
components.
Certification Areas Class 1 - Flammable Gas or Vapor, Division 1 - Intermittent Hazard
Gas Groups B, C, D Ensures safety for Hydrogen, Ethylene and Propane in environment
IEC Robinson Pressure Switch has been tested to international standards.
External Adjustment Simply rotate knurled adjustment collar to increase or decrease pres-
sure setting.
Security/Lockout
To prevent tampering or unauthorized use of the Pressure Switch a Car
Seal lockout devise can be installed on three components 1) electrical
enclosure cover 2) calibration screw/cap, and 3) set point adjustment
collar.
Process Connection NACE
(for sour service)
Process Connection Materials are chosen in accordance to NACE
MR0175-2003
Piston Orientation Eliminate the need for pulsation dampening
Field Service Microswitch replaceable, no need to disassemble Pressure Switch.
Diaphragm Servicing
Diaphragm can be replaced without disassembling Pressure Switch ,
Pin socket available for Diaphragm Nut, contact Robinson Pressure
Controls.
Low Ownership Costs Maintenance kits are available to renew Pressure Switch for service.
8 Features
7 Recommend Service
7.1 3 month interval - Verify operation by pressure testing, most importantly prior to cold
weather season.
7.2 Ensure Annunciation port (breathe cap/check valve) is free from obstruction.
7.3 Any amount of leakage no matter how slight indicates a primary seal failure and the
switch will need to be removed from service and rebuilt.
A minimum of 1.5 psi is required for the Check Valve to Annunciate
ZIMCO INSTRUMENTATION INC.
11141 15 Street NE, Calgary, AB, T 3K 0Z5, Canada
Phone: [phone] Email: [email protected] Website: www.zimco.ca

7
Important information
Robinson Controls Inc. has established industry leadership in the design and manufacture of its prod-
ucts. When properly selected, this Robinson product is designed to perform its intended function safely
during its useful life. However, the purchaser or user of Robinson products should be aware that Robin-
son products might be used in numerous applications under a wide variety of industrial service condi-
tions. Although Robinson can provide general guidelines, it cannot provide specific data and warnings
for all possible applications. The purchaser/user must therefore assume the ultimate responsibility for
the proper sizing and selection, installation, operation, and maintenance of Robinson products. The pur-
chaser/user should read and understand the Installation Instructions included with the product, and train
its employees and contractors in the safe use of Robinson products in connection with the specific appli-
cation.
While the information and specifications contained in this literature are believed to be accurate, they are
supplied for informative purposes only and should not be considered certified or as a guarantee of satis-
factory results by reliance thereon. Nothing contained herein is to be construed as a warranty or guaran-
tee, express or implied, regarding any matter with respect to this product. Because Robinson is continu-
ally improving and upgrading its product design, the specifications, dimensions and information con-
tained herein are subject to change without notice. Should any question arise concerning these provi-
sions, the purchaser/user should contact the Robinson Controls Inc. factory at:
Robinson Controls Inc
#104 - 7609 Sparrow Dr
Leduc, Alberta, Canada T9E 0H3
ZIMCO INSTRUMENTATION INC.
11141 15 Street NE, Calgary, AB, T3K 0Z5, Canada
Phone: [phone] Email: [email protected] Website: www.zimco.ca