Series PTG Differential Pressure Piston-Type Gage
Specifications - Installation and Operating Instructions
Bulletin A-41
The Series PTG Differential Pressure Piston-Type Gage can be used to
measure the pressure drop across filters, strainers, pump performance testing,
and heat exchanger pressure drop monitoring. Its simple, rugged design
possesses a weather and corrosion resistant gage front with a shatter resistant
lens. The Series PTG contains a piston-sensing element, which provides different
differential pressure ranges with full-scale accuracies of ±2% to ±5%. Constructed
from aluminum or 316 Stainless Steel and available with two 1/4˝ FNPT end
connections, the Series PTG provides over-range protection rated to 5000 PSIG
(340 bar) or 6000 PSIG (400 bar) depending on model.
INSPECTION
Before installation check the nameplate on each instrument against the receiving
paperwork and the intended application for correct part number, materials of
construction, working pressure, dial range, etc. Inspect for shipping damage and,
if damaged, report it immediately.
INSTALLATION
The Series PTG is calibrated and tested prior to shipment and is ready for
immediate installation. Use of the following installation procedures should eliminate
potential damage and provide optimum trouble-free operation.
1. PROCESS CONNECTIONS: 1/4" FNPT are provided as standard. There are two
connections on the housing identified as "hi" and "lo" for high pressure and low
pressure. Be sure to get these plumbed to the proper connections on your
system. Improper connection will not damage the instrument, but it will not
function properly. Flexible tubing is recommended to minimize the effect of
possible vibration.
2. INSTRUMENT LOCATION: On liquid service, the instrument should be mounted
below the process connections to facilitate self-bleeding. On gas service, it should
be located above the process connections to promote self-draining. If the process
contains particulates, a "pigtail" loop or drop leg (manometer "U-tube"
configuration) in the tubing will minimize the possibility of it migrating into the
instrument.
3. PANEL MOUNTING: Gages with 2-1/2" dials can only be mounted through the
rear of the panel. Make the proper panel cutout as indicated in (Fig .1). Remove
the (4) bezel screws. Insert the gage front through the rear of the panel and reinstall
the bezel screws through the front of the panel and into the gage bezel. Tighten
the screws securely, alternating in a diagonal pattern.
Gages with 4-1/2" dial should be mounted from the front of the panel. Make the
cutout as indicated in (Fig. 1). Insert the (4) panel mounting studs, finger tight, into
the metal inserts located in the rear of the bezel. Insert the gage through the panel,
aligning the panel mounting studs with the holes in the panel. Install the (4) #8-32
nuts onto the studs and tighten securely.
TROUBLESHOOTING
A. Check for proper hook up, high to "hi" low to "lo".
B. Make sure that certain block valves are open.
C. If A & B check out correctly, loosen high-pressure line to determine if there is
pressure to the instrument.
D. Verify that the gage is not in an electromagnetic/magnetic environment.
i.e.; close proximity to high current power lines.
MAINTENANCE
The Series PTG differential pressure gages are 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 number before shipping.
DWYER INSTRUMENTS, INC.
Phone: 219/879-8000 www.dwyer-inst.com
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: 219/872-9057 e-mail: info@dwyer-inst.com
Service: Compatible gases and liquids.
Wetted Materials: Gage body – Aluminum or 316L SS (only aluminum for Series
PTGC).
Piston – 316L SS.
Spring – 316L SS.
Ceramic Magnet.
End Plugs- Aluminum (Aluminum Body); 316L SS (SS Body);
only Aluminum for Series PTGC.
Seals- Buna-N (standard).
Dial Case: “Engineered Plastic” with shatter-resistant acrylic lens.
Accuracy: ±3-2-3% (Series PTGA & PTGB) of full scale in accordance with ASME
B40.100 Grade B; ±5% of full scale ascending (Series PTGC).
Pressure Limits: Working pressure: 5000 PSIG (340 bar) - Series PTGA & PTGC;
6000 PSIG (400 Bar) - Series PTGB. Proof Pressure: 10,000 PSIG (689 bar) - Series
PTGA & PTGC; 12,000 PSIG (827 Bar) - Series PTGB.
Temperature Limits: -40 to 200 ˚F (-40 to 93 ˚C).
Size: 2.5˝ (63 mm) 4.5˝ (115 mm).
Mounting Orientation: Mount in any position.
Process Connections: 1/4˝ Female NPT end connections.
Weight: Aluminum - 2.5˝ x 0.60 lbs (0.27 kgs), 4.5˝ x 0.95 lbs (0.43 kgs); 316 SS -
2.5˝ x 1.35 lbs (0.61 kgs), 4.5˝ x 1.60 lbs (0.73 kgs).
PANEL CUTOUT
4X 13/64 [5.16]
EQUALLY SPACED
ON A Ø3-1/2 [88.9]
BOLT CIRCLE
Ø3-1/32
[Ø76.99]
CUTOUT
LOW
HIGH
3-3/8
[85.73]
4-15/16
[125.41]
2-1/2” DIAL SIZE
Ø3
[Ø76.2]
1-63/64
[50.4]
1/2
[12.7]
1/8
[3.18]
Ø3-5/16
[Ø84.14]
HIGH
1
[25.4]
4X 13/64 [5.16]
EQUALLY SPACED
ON A Ø3-1/2 [88.9]
BOLT CIRCLE
PANEL CUTOUT
5-5/16
[134.94]
CUTOUT
4-1/2” DIAL SIZE
Ø6-15/64
[Ø158.35]
Ø5-1/4
[Ø133.35]
HIGH
1-31/64
[37.7]
Series PTGA
Series PTGB
Series PTGC
©Copyright 2007 Dwyer Instruments, Inc. Printed in U.S.A. 9/07 FR# R1-443576-00
Fig. 1
A-41 9/7/07 1:03 PM Page 1
1
Dwyer Series A4 User manual