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DwyerMeasurement

Dwyer Transmitter 645-1

The Dwyer Transmitter 645-1 is a differential pressure transmitter for liquids, offering a 0–2 psid (0–0.14 bar) measurement range with ±0.25 % accuracy. It features a 3-valve brass manifold, 1/4"-18 female NPT…

SKU 3G-CBM-02199

Also listed as: DWY 26004 · DWY-26004

Brand
Dwyer
Item
Transmitter 645-1
Category
Measurement
UNSPSC
41112412 — Pressure gauge
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Local availability & support

Delivery
Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
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Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

Dwyer
type
differential pressure transmitter for liquids
model
645-1
range
0–2 psid (0–0.14 bar)
accuracy
±0.25 %
manifold
3-valve, brass
connection
1/4"-18 female NPT
enclosure rating
IP65
response time ms
30–50
enclosure material
stainless steel/aluminium
loop resistance ohm
0–1000

Datasheet Content

Transmetteur de pression différentielle pour liquides Série 645 ±0.25% de précision, réponse rapide, basse pression 1-63/64 ø7/8 KNOCKOUT INTENDED FOR [50.50] 1-1/2 A 1/2 I.D. CONDUIT CONNECTION [38.16] 1-3/32 DWYER INSTRUMENTS, INC. MICHIGAN CITY, IN. U.S.A. 2 5/32 1-15/16 [27.98] [54.61] [49.35] 3-1/16 [77.59] 3 1/64 [76.45] 1 [25.44] 1/4 NPT HIGH LOW BOTH SIDES 2-7/16 1 PRESSURE [62.01] PRESSURE PORT PORT BLEED SCREWS [25.44] La série 645 Transmetteur de Pression Différentielle pour liquides est conçue SPÉCIFICATIONS pour un usage compatible avec les gaz et liquides et utilisée tant pour la mise en pression que Service : Gaz et liquides compatibles pour l’usage en pression comme en référence. comme ports de référence. La sonde capacitive à réponse rapide délivre un signal de sortie de 4 à Matériaux : 17-4 PH acier inoxydable, Série 300 acier inoxydable, élastomères fluorés et joints 20 mA proportionnel à la pression différentielle avec ±0.25% de précision. La série de transmetteurs toriques en silicone and joints de vis d’extraction. Précision : ±0.25% FS (RSS). 645 est idéale pour les contrôles de procédé, la surveillance de l’état des filtres, le matériel de Limites de Température : Opérationnelle : de -22 à +80°C ; Stockage : de -54 à réfrigération, le contrôle de débit de pompe, l’équipement HVAC et la mesure des niveaux de liquide. +126°C. Limites de Pression : (Côté haut) de 0,06 à 0,34 bar : 20 x FS, Afin de faciliter l’installation et l’entretien, commandez le collecteur 3 vannes proposé en option. 10 à 25 psi : 10 x FS, 50 psi : 5 x FS, 100 psi : 2.5 x FS ; (côté bas) 2.5 x FS. La prise de prélèvement permet l’élimination totale de l’air dans les tubes et cavités sous pression. Effets Thermiques : (inclus le zéro et l’étendue) ±0.02% FS/°F, de -1 à +65°C. Puissance Requise : de 11 à 30 VDC. Signal en sortie : de 4 à 20 mA, 2 fils. Modèle Description Bar Réf. Réglages du zéro et de l’étendue : Réglables, ±1 mA, non interactif. 645-0 0 à 1 psid 0 à 0,069 DWY26002 Temps de Réponse : de 30 à 50 ms. Résistance de Boucle : de 0 à 1000Q. Connection Electrique : Bloc de jonction avec bande de cloison et conduit de boîtier. 645-1 0 à 2 psid 0 à 0,14 3G-CBM-02199 22 mm d’ouverture de diamètre du conduit. Raccord : 1/4”-18 femelle NPT. 645-2 0 à 5 psid 0 à 0,35 DWY26006 Boîtier : Acier inoxydable/aluminium, IP65. Poids : 0.4 kg. 645-3 0 à 10 psid 0 à 0,69 DWY26008 Homologations : CE. 645-4 0 à 25 psid 0 à 1,72 DWY26010 Collecteur 3 vannes, vannes multiples. Collecteur : Laiton. Type de Valve : 90° on/off. Raccord : 1/4”-18 femelle NPT. 645-5 0 à 50 psid 0 à 3,45 DWY26012 645-6 0 à 100 psid 0 à 6,90 DWY26014 OPTION Pour un certificat d’étalonnage traçable selon les prescriptions NIST, utiliser le code de commande NISTCAL-PT1.

Technical Documents

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Dwyer Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The Dwyer Transmitter 645-1 is a differential pressure transmitter for liquids, offering a 0–2 psid (0–0.14 bar) measurement range with ±0.25 % accuracy. It features a 3-valve brass manifold, 1/4"-18 female NPT connection, stainless steel/aluminium IP65 enclosure, 30–50 ms response time, and 0–1000 ohm loop resistance. 3G Electric supplies this unit to Singapore and Southeast Asia industrial operations, handling full delivery and documentation.

Frequently Asked Questions

Where can I buy the Dwyer 645-1 transmitter worldwide?

3G Electric is an authorised distributor of Dwyer measurement products. We source the Dwyer 645-1 differential pressure transmitter and handle worldwide delivery, customs clearance, and logistics. Lead time on request.

What is the measurement range and accuracy of the Dwyer 645-1?

The Dwyer 645-1 offers a 0–2 psid (0–0.14 bar) range with ±0.25% accuracy. It has a 30–50 ms response time and 0–1000 ohm loop resistance, suitable for low-pressure liquid applications.

What connection type does the Dwyer 645-1 transmitter use?

The Dwyer 645-1 features a 1/4"-18 female NPT connection with a 3-valve brass manifold. The stainless steel and aluminium enclosure is IP65 rated, offering protection for indoor and outdoor industrial environments.

Used in

Common applications for Dwyer
Combustion air-filter monitoring — Magnehelic Series 2000 on burner air-intake filter banks
Clean-room and pharmaceutical pressurisation — Magnehelic / Capsuhelic differential-pressure gauges
HVAC fan-discharge static pressure — Mark II inclined-vertical manometers on AHU test points
Filter-blockage alarms — Photohelic Series 3000 combined gauge/switch on air-handling units
BMS-integrated pressure monitoring — Digihelic DH3 with 4–20 mA output for building management

Dwyer Products

3G Electric supplies Dwyer measurement. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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