Introduction
Diagram showing a cross-section of the Series P/G Ultra Mag™ Level Switch. Key components labeled include a 'Driving magnet' and a 'Driven magnet' separated by a nonferrous wall. A 'Sealed junction box' is visible, along with an 'Epoxy seal' and a 'Sealed switch cavity'.
The Series P/G Ultra Mag™ Level Switch provides level indication by detecting pressure applied by the bulk material to the sensing diaphragm. The switch is tripped magnetically, as the result of 2 magnets with like poles repelling one another. The fields of the magnets perform through the nonferrous wall of the switch housing. Pins, links and O-rings, which often cause failure due to moisture, dirt, and corrosion, are eliminated. The switch enclosure is completely sealed.
How it Works
Unit Performs As Follows:
- When the diaphragm is forced inward by the product bulk material, the "driving" magnet moves inward, as does its magnetic field.
- The field of the "driving" magnet repels the field of the "driven" magnet attached to the switch arm, and the switch is tripped.
- Deactivation occurs when product is removed from the vessel and the diaphragm and "driving" magnet returns to their original positions.
Adjustments
Sensitivity Adjustment ⚙️
The P/G Ultra Mag™ offers a sensitivity adjustment that is accessible from outside of the bin and easily adjusted with a screwdriver. This enables the user to adjust the sensitivity of the unit, should vessel contents change, without removing the unit from the vessel. Turning the adjustment screw inward increases operating forces, and turning the screw outward decreases operating forces. A maximum of 4 turns is available. When the screw is bottomed, the force is at a maximum. With 4 turns out the diaphragm force is at a minimum. Normal setting is two turns out. See Figure 1.
Switch Adjustment ⚙️
The switch adjustment determines whether actuation occurs early in diaphragm travel or late. Turning the screw inward retards action and causes the switch to trip late. Backing the screw out results in early actuation when the diaphragm is slightly depressed. A center switching position is desirable.
Regardless of the position (angle) in which the control is eventually mounted, the switch should trip at mid travel of the diaphragm. "Break" (switch off) should never occur within the last 1/4 of travel outward. "Make" (switch on) should not occur after 3/4 travel inward.
Diagram illustrating the diaphragm and switch adjustment mechanism. Labeled parts include 'DIAPHRAGM ADJUSTMENT', 'SWITCH ADJUSTMENT SPRING', and 'SWITCH ADJUSTMENT SCREW'.
Mounting ⬆️
A choice of either suspension or flange mounting is available to match your application. Flange mounting is the best choice for control of low or intermediate level in vessels containing granular product that does not "bridge", "rathole", or otherwise build up on vessel walls. Choose suspension mounting for high level in vessels and for better operation with "bridging" product. Note that the mounting configuration is represented by the letter "S" for suspension or "F" for flange.
Diagrams for suspension mounting (models P-S-D-A; G-S-D-A). Includes 'REAR VIEW', 'LEFT SIDE VIEW', and 'FRONT VIEW'. Key features shown are a 'SUSPENSION PIPE 1" NPT', 'CONDUIT ENTRANCE 1/2 NPT', and dimensions like 7-1/2" DIA, 7-1/4" DIA, and 3-3/8".
Diagrams for flange or side mounting (models P-F-D-A; G-F-D-A). Includes 'REAR VIEW', 'RIGHT SIDE VIEW', and 'FRONT VIEW'. Key features shown are 'MOUNTING HOLES [6] 5/16" DIA ON 8-3/8" DIA BOLT CIRCLE', 'JCT. BOX COVER', 'SWITCH CAVITY COVER', and dimensions like 9-1/8" DIA, 7-1/4" DIA, and 3-3/8".
Specifications ⚙️
| Attribute | Details |
|---|---|
| Service | Compatible powder or bulk solids. |
| Wetted Materials | Mounting flange: Aluminum or 304 SS; Diaphragm: Urethane, Buna-N, PTFE, silicone rubber, polyester, fluoroelastomer, white Buna-N (food grade ?), or EPDM. |
| Temperature Limits ?️ | Depends on diaphragm material. Standard switch: -40 to 185°F (-40 to 85°C); High temperature switch: -40 to 350°F (-40 to 176°C). |
| Pressure Limit ⚖️ | 60 psig (4.14 bar). |
| Enclosure Rating ?️ | General purpose or weatherproof and explosion-proof. |
| Electrical Connections ? | 18 gage solid core, 600 V TEW 105°C, style 1015. Epoxy sealed at conduit entrance. 12" (304.8 mm) long. |
| Conduit Connection ? | 1/2" female NPT. |
| Process Connection | For flanged models standard is 8-3/8" (212.725 mm) diameter bolt hole circle. |
| Mounting Orientation ? | Flange mount or suspend depending on model. |
| Set Point Adjustment ? | Internal screw. |
| Weight ⚖️ | 7 lb (3.18 kg). |
| Options ✨ | Suspension kits and flange adaptor rings. |
| Agency Approvals ✅ | UL. |
Wiring ?
The P/G Ultra Mag™ has a 1/2" NPT conduit connection. Remove the back plate to access the single pole double throw snap-switch. The switch rating is: 15A @ 125, 250, or 480 VAC. There are three terminals on the snap-switch: "Common", "Normally Open", and "Normally Closed".
Diagram showing electrical connections for the switch. Labeled as 'ELECTRICAL CONNECTIONS [REAR VIEW] NTS'. Terminals are shown as 'COMMON', 'NORMALLY OPEN', and 'NORMALLY CLOSED'.
Electrical rating 15 AMPS @ 125, 250, OR 480 VAC.
Maintenance ?️
The P/G Ultra Mag is not field serviceable and should be returned if repair is needed (field repair should not be attempted and may void warranty). Be sure to include a brief description of the problem plus any relevant application notes. Contact customer service to receive a return goods authorization (RGA) number before shipping.
Dwyer Instruments, Inc.
P.O. BOX 373 MICHIGAN CITY, INDIANA 46360, U.S.A.
? Phone: 219-879-8000 | ? Fax: 219-872-9057 | ? www.dwyer-inst.com | ✉️ e-mail: info@dwyermail.com
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