APG RPM Resistive Continuous Float Level Transmitter Installation Guide

Description
The RPM utilizes reed switches in the instrument’s stem and a permanent magnet in the float. As the float rises or falls with the level of the liquid, the magnet inside the float acts on the reed switches inside the stem and provides a resistive-chain voltage output. The RPM is also available with optional electronics that convert the resistance output into a 4-20mA signal.

How To Read Your Label
Each label comes with a full model number, a part number, and a serial number. The model number for the RPM will help you identify your exact configuration. Compare the model number to the options on the datasheet to determine your setup.

Warranty
The product is covered by APG’s warranty against defects for 24 months. For more information, visit their
Warranty page.

Product Usage Instructions

Mounting and Installation Instructions
The RPM should be installed indoors or outdoors in an area that meets specified conditions.

Dimensions
Detailed information about the dimensions and mounting brackets is provided in the manual.

Wiring Terminals for Voltage Operation
Follow wiring drawings (Explosion Proof or Intrinsically Safe) for proper installation to maintain safety approvals and ratings.

Frequently Asked Questions

Q: What should I do if I encounter issues with my RPM transmitter?
A: If you face any problems, refer to the troubleshooting section in the manual or contact technical support at 888-525-7300 for assistance.

Q: Can I install the RPM transmitter outdoors?
A: Yes, you can install it outdoors as long as it meets the specified conditions mentioned in the manual.

Thank You
Thanks for purchasing an RPM resistive continuous float level transmitter from us! We appreciate your business and your trust. Please take a moment to familiarize yourself with the product and this manual before installation. If you have any questions, don’t hesitate to call us at 888-525-7300.

To see full product manuals, go to https://www.apgsensors.com/resources-user-manuals/

Description

The RPM utilizes reed switches in the instrument’s stem and a permanent magnet in the ﬂoat. As the ﬂoat rises or falls with the level of the liquid, the magnet inside the ﬂoat acts on the reed switches inside the stem and provides a resistive-chain voltage output. The RPM is also available with optional electronics that convert the resistance output into a 4-20mA signal.

How To Read Your Label

Each label comes with a full model number, a part number, and a serial number. The model number for the RPM will look something like this:

SAMPLE: RPM-96-A-F-AIS-011-0-2-00

The model number correlates with all the conﬁgurable options and tells you exactly what you have. Compare the model number to the options on the datasheet to identify your exact conﬁguration. You can also call us with the model, part, or the serial number, and we can help you.
You’ll also ﬁnd all hazardous certiﬁcation information on the label.

Warranty

This product is covered by APG’s warranty to be free from defects in material and workmanship under normal use and service of the product for 24 months. For a full explanation of our Warranty, please visit https://www.apgsensors.com/resources/warranty-certiﬁcations/warranty-returns/. Contact Technical Support to receive a Return Material Authorization before shipping your product back.

Dimensions

Mounting and Installation Instructions

The RPM should be installed in an area — indoors or outdoors — which meets the following conditions:

Ambient temperature between -40°F to 185°F (-40°C to 85°C) (For explosion proof models: ambient temperature between -40°F to -104°F [-40°C to -40°C])
Relative humidity up to 100%

Altitude up to 2000 meters (6560 feet)
IEC-664-1 Conductive Pollution Degree 1 or 2

IEC 61010-1 Measurement Category II
No chemical corrosive to stainless steel (such as NH3, SO2, Cl2, etc.)

Ample space for maintenance and inspection

Additional care must be taken to ensure:

The sensor is located away from strong magnetic ﬁelds, such as those produced by motors, transformers, solenoid valves, etc.
The medium is free from metallic substances and other foreign matter.
The sensor is not exposed to excessive vibration.
Do not locate your RPM sensor near inlets/outlets.

Mounting Instructions:

Clamp Mounting: Tighten a U-bolt stainless steel mounting bracket around the RPM’s stem, just below the union.
Flange Mounting: Provide the compatible mating ﬂange on the tank and install using a suitable gasket.
Plug Mounting: Provide the compatible female boss on the tank and install the probe with thread tape.

Installation Notes:

If there is surface wave action, then use a time-delay relay or stilling tube. If a stilling tube is used, drill vent holes in the tube and use a spacer to assure the ﬂoat has free travel inside the tube (See Figure 5.1).

DANGER: Do not remove the housing cover until the atmosphere is determined safe and the power supply is turned off.

Wiring Terminals for Voltage Operation

The wiring of your RPM is as follows:

Red and black wires connect to each end of a resistive chain.
The white wire is the voltage output that is connected to different points on the resistive chain by reed switches.

Red Wire: +5 to +24 VDC
Black Wire: Ground
White Wire: Voltage Out

IMPORTANT: Your RPM MUST be installed according to drawing 9001415 (Explosion Proof Wiring Drawing) or 9001414 (Intrinsically Safe Wiring Drawing) to meet listed approvals. Faulty installation will invalidate all safety approvals and ratings.

Wiring Terminals for 4-20 mA Output

The wiring of your RPM is as follows:

4-20 mA Out: terminal out
+24 VDC: 24V

Offset and Span Calibration

(4-20 mA output probes only)

This procedure can be performed in a non-hazardous area, either prior to installation, or by temporarily uninstalling your 4-20 mA RPM probe:

Set DC power supply to 24 VDC, and connect to the RPM probe, with ammeter in loop.

Move ﬂoat to the desired position for 4 mA output.
Using a jeweler’s screwdriver or a suitable instrument, adjust the “Offset“ potentiometer until you have a 4 mA output.
Move ﬂoat to the desired position for 20 mA output.

Using a jeweler’s screwdriver or a suitable instrument, adjust the “Span“ potentiometer until you have a 20 mA output.
Repeat as necessary to ﬁne tune calibration.
Replace the housing cover when ﬁnished.

NOTE: This procedure can be performed in a non-hazardous area, either prior to installation, or by temporarily uninstalling your 4-20 mA RPM probe.

NOTE: You may also return the RPM probe to the factory for repair and/or adjustment.

Removal Instructions

Removing your RPM from service must be done with care. It’s easy to create an unsafe situation, or damage your sensor, if you are not careful to follow these guidelines:

Ensure all circuits are de-energized, and any hazardous atmosphere has dispersed.
Disconnect wires, either at terminals in the RPM head or at your system.
Remove the RPM with an appropriately sized wrench (per your mounting type).

Clean the RPM’s stem and ﬂoat of any debris (see General Care) and inspect for damage.
Store your RPM in a dry place, at a temperature between -40° and 85°C (-40° and 185°F).

General Care

Your RPM resistive continuous ﬂoat level transmitter is very low maintenance and will need little care as long as it is installed correctly. However, in general, you should:

Periodically inspect the stem and ﬂoats for any trapped debris, sediment, or other foreign material.
Avoid applications for which the RPM was not designed, such as extreme temperatures, contact with incompatible corrosive chemicals, or other damaging environments.
If your RPM has an NPT mount, inspect the threads whenever you remove it from duty or change its location.

Never leave the housing cover off. If the cover is damaged or lost, order a replacement immediately.

Repair Information

Should your RPM require service, please contact us via email, phone, or online chat on our website. We will issue you an RMA number with instructions.

WARNING: SUBSTITUTION OF COMPONENTS MAY IMPAIR INTRINSIC SAFETY; AVERTISSEMENT — LA SUBSTITUTION DE COMPOSANTS PEUT COMPROMETTRE LA SECURITE INTRINSEQUE.

DANGER: OPEN CIRCUIT BEFORE REMOVING COVER or KEEP COVER TIGHT WHILE CIRCUITS ARE ALIVE;

AVERTISSEMENT — COUPER LE COURANT AVANT D’ENLEVER LE COUVERCLE, ou GARDER LE COUVERCLE FERME TANT QUE LES CIRCUITS SONT SOUS TENSION.

DANGER: EXPLOSION HAZARD-DO NOT DISCONNECT WHILE CIRCUIT IS LIVE UNLESS AREA IS KNOWN TO BE NON-HAZARDOUS;

AVERTISSEMENT — RISQUE D’EXPLOSION. NE PAS DEBRANCHER TANT QUE LE CIRCUIT EST SOUS TENSION, A MOINS QU’IL NE S’AGISSE D’UN EMPLACEMENT NON DANGEREUX.

IMPORTANT: SEAL SHALL BE INSTALLED WITHIN 50 mm OF THE ENCLOSURE; IMPORTANT — UNSCELLEMENT DOIT ETRE INSTALLE A MOINS DE 50 mm DU BOITIER.

Speciﬁc Conditions of Use

Parts of the enclosure are manufactured from aluminium. In rare cases, ignition sources due to impact and friction sparks could occur. This shall be considered during installation, particularly if the equipment is installed in a zone 0 location.
Under certain extreme circumstances, the non-metallic parts incorporated in the enclosure of this equipment may generate an ignition-capable level of electrostatic charge. Therefore the equipment shall not be installed in a location where the external conditions are conducive to the build-up of electrostatic charge on such surfaces. Because the non-conductive surface of the ﬂoat may be charged by non-conductive media, it has to be assured that the media is electrostatically conductive. This is particularly important if the equipment is installed in a zone 0 location. In addition, the equipment shall only be cleaned with a damp cloth.
The sensor tube shall be reliably connected to the potential equalizing system to ensure that it is not an isolated part.

Hazardous Location Wiring

Explosion Proof Wiring Drawing

Installation in Class | Division 2 Groups
C and D, Max. Temp. 85°C
Installation in Class | Division 1 Groups C and D, Max. Temp. 40°C
Installation in Class 1 Zone 1; Ex d lIB / AEx d lIB T3

Install in accordance with CEC,NEC articles 504, 505 and ISA RP12.6 Recommended
Practice for the Installation of Intrinsically Safe Circuits.
WARNING: SUBSTITUTION OF COMPONENTS MAY IMPAIR INTRINSIC SAFTEY

WARNING: EXPLOSION HAZARD – DO NOT DISCONNECT EQUIPMENT UNLESS POWER
HAS BEEN SWITCHED OFF OR AREA IS KNOWN TO BE NONHAZARDOUS
WARNING: POTENTIAL ELECTROSTATIC CHARGING HAZARD – Do not clean float with a dry cloth

Do Not Alter without proper approval from the ATEX
Authorized Person.

Documents / Resources

APG RPM Resistive Continuous Float Level Transmitter [pdf] Installation Guide
RPM-96-A-F-AIS-011-0-2-00, RPM Resistive Continuous Float Level Transmitter, RPM, Resistive Continuous Float Level Transmitter, Continuous Float Level Transmitter, Float Level Transmitter, Level Transmitter, Transmitter

References

User Manual

APG RPM Resistive Continuous Float Level Transmitter