RTDs / Probe RTDs : Series 21 1/4” dia.

Series 21: 1/4” dia. Industrial Platinum RTD Probes

PNs 21A, 21B, 21C, 21D, 21H


Ordering Specifications

STRAIGHT PROBE ASSEMBLIES
TYPE 21A

Features: 1/4" dia. 316 SS sheath; operating range –320°F to 900°F, Teflon® insulated lead wires; single or dual elements, RdF Reference or IEC/DIN R vs. T characteristics, and 2, 3 or 4 wire element configurations.

RIGID PROBE ASSEMBLIES WITH
HERMETICALLY SEALED CONNECTOR
TYPE 21C

‍ ‍

Features: 1/4" dia. 316 SS sheath with hermetically sealed 4-pin connector; operating range –320°F to 900°F single or dual elements; RdF Reference or IEC/DIN R vs. T characteristics, and 2, 3 or 4 wire configurations.
*P/N 53105 (Mating Connector) must be ordered separately.

HERMETICALLY SEALED
PROBE ASSEMBLIES
TYPE 21H

Features: 1/4" dia. SS sheath; operating range –320°F to 900°F; Teflon® insulated 3-conductor cable; RdF Reference or IEC/DIN R vs. T characteristics. Integral hermetic seal. Single element only.

Ordering Specifications

 21A/C/H
  RTD RESISTANCE SPECIFICATIONS (Ohms @ 0°C)
  10    100 ± 0.1 (α = 0.003924 Ω/Ω/°C) RdF Ref. Std.
  11    100 ± 0.1 (α = 0.00385 Ω/Ω/°C) IEC/DIN Std.
  T01   100 + 0.12 (α = 0.00385 Ω/Ω/°C) thin film
  20    200 ± 0.2 (α = 0.003924 Ω/Ω/°C)
  21    200 ± 0.2 (α = 0.00385 Ω/Ω/°C)
  T05   500 ± 0.6 (α = 0.00385 Ω/Ω/°C) thin film
  T10   1000 ± 1.2 (α = 0.00385 Ω/Ω/°C) thin film
  102*  100 ± 0.1 Dual Element (α = 0.003924 Ω/Ω/°C)
  112*  100 ± 0.1 Dual Element (α = 0.00385 Ω/Ω/°C)
  T012* 100 ± 0.12 Dual Element (α = 0.00385 Ω/Ω/°C) thin film
       *Not Available on 21H
 SERVICE PARAMETER – Sinusoidal Vibration 20Hz to 2kHz
  S  Standard construction (25 g wire-wound, 80 g thin film)
  H  Heavy-duty construction (up to 50 g)
     (1 wire element only)
 PROBE LENGTH (Specify “L” in inches) 
      Std. Const: 3" minimum,
      Heavy Duly: 3" minimum for 21H,
      4" minimum for 21A & 21C (see photos)
 LEAD WIRE CONFIGURATION
A Single element, 2 wires, any length
B* Single element, 3 wires,
(36" or under on 21A),
*21H requires B cable, any length,
standard.
C Single element, 4 wires,
(36" or under on 21A)
D Dual element, 2 wires per element
E Dual element, 3 wires per element,
21A only
 ARMOR LENGTH (21A only)
     Specify “X” in inches (ie. A0= no armor,
     A60 = 60 inches) (Single element only)
 LEAD LENGTH - Specify in inches
     (Not applicable to 21C)
21A
10
S
4
B
A60
60
 Typical write-up for 21A
21C
T10
S
4
C
-
60
 Typical write-up for 21C

RIGID PROBE ASSEMBLIES
WITH HEX FITTING
TYPE 21B ‍ ‍

Features: 1/4" dia. 316 SS sheath; operating range –320°F to 900°F, Teflon® insulated lead wires; single or dual elements, RdF Reference or IEC/DIN R vs. T characteristics, and 2, 3 or 4 wire element configurations.

Ordering Specifications

21B 14" Diameter Sheathed Platinum Probe, Rigid Mount to Fitting
 
     RTD RESISTANCE SPECIFICATIONS (Ohms @ 0°C)
10
11
T01
20
21
T05
T10
102
112
T012
100 ± 0.1 (α = 0.003924 Ω/Ω/°C) RdF Ref. Std.
100 ± 0.1 (α = 0.00385 Ω/Ω/°C) IEC/DIN Std.
100 ± 0.12 (α = 0.00385 Ω/Ω/°C) thin film
200 ± 0.2 (α = 0.003924 Ω/Ω/°C)
200 ± 0.2 (α = 0.00385 Ω/Ω/°C)
500 ± 0.6 (α = 0.00385 Ω/Ω/°C) thin film
1000 ± 1.2 (α = 0.00385 Ω/Ω/°C) thin film
100 ± 0.1 Dual element (α = 0.003924 Ω/Ω/°C)
100 ± 0.1 Dual element (α = 0.00385 Ω/Ω/°C)
100 ± 0.12 Dual element (α = 0.00385 Ω/Ω/°C) thin film
 
    CONNECTION HEAD (see connection head table below)
    SERVICE PARAMETER - Sinusoidal Vibration 20Hz to 2kHz
S
H
Standard construction (25 g wire-wound, 80 g thin film)
Heavy duty construction (up to 50 g) (single wire element only)
 
    PROBE LENGTH
(Specify “L” in inches, >60" requires support) (see photo)
Std. Const: 3" min, Heavy Duty: 4" min.
    NUMBER OF LEADS
A
B
C
D
E
X3
AX3
X4
AX4
Single element, 2 wires any length
Single element, 3 wires 36" or under in length
Single element, 4 wires 36" or under in length
Dual element, 2 wires per element
Dual element, 3 wires per element
Single element, 3 wire cable over 36"
Adds stainless steel armor excluding last 5"
Single element , 4 wire cable over 36"
Adds stainless steel armor excluding last 5"
    ARMOR LENGTH
           Specify “X” in inches (ie. A0= no armor,
           A60 = 60 inches) (Single element only)
    LEAD LENGTH - Specify in inches (4" Standard)
21B
11
D
S
6
B
A0
4
  Typical Write-up for 21B

Connection Heads with Terminals‍ - NEMA 4 with Gasket‍ ‍

CODE to order with sensor: to order alone: Conduit Max.Temp
A Small cast aluminum head P/N 51590-1 1/2 NPT 125 ° C
B High temp. small cast aluminum head P/N 51590-2 1/2 NPT 260 ° C
C Cast Iron head P/N 51840-1 3/4 NPT 260 ° C
D For no connection head specify "D"
E Large cast aluminum head P/N 52298-1 3/4 NPT 260 ° C
F Economy Conduit body P/N 41438 1/2 NPT 125 ° C
G Explosion proof small cast aluminum head P/N 41333-1 1/2 NPT 125 ° C
H High temp. expl. proof small cast aluminum head P/N 41333-2 1/2 NPT 260 ° C
I Hinged plastic P/N 54684 3/4 NPT 125 ° C
J Hinged cast aluminum P/N 54681 3/4 NPT 125 ° C
K Din B cast aluminum P/N 55261 1/2 NPT 100 ° C
S Other (please specify when ordering)
T Transmitter, specify or supply w/head

Terminals: All heads include at least 4 two-screw starp terminations. 6 can be requested in styles “C” and “E”. Style “K” includes 6 two-screw post straps.Style “A”, “B”,”G” & “H” can have up to 8 screw-in post straps.

SPRING LOADED PROBE ASSEMBLIES
WITH HEATING
TYPE 21D

Features: 1/4" diameter 316 SS sheath; operating range –320°F to 900°F with universal hardware for spring-loading; single or dual elements;

RdF Reference or IEC/DIN R vs T characteristics, and 2, 3 or 4 wire element configurations. Styles A & B Head Shown.

21D 1/4" Diameter Sheathed Platinum Probe, Spring-Loaded
 
     RTD RESISTANCE SPECIFICATIONS (Ohms @ 0°C)
10
11
T01
20
21
T05
T10
102
112
T012
100 ± 0.1 (α = 0.003924 Ω/Ω/°C) RdF Ref. Std.
100 ± 0.1 (α = 0.00385 Ω/Ω/°C) IEC/DIN Std.
100 ± 0.12 (α = 0.00385 Ω/Ω/°C) thin film
200 ± 0.2 (α = 0.003924 Ω/Ω/°C)
200 ± 0.2 (α = 0.00385 Ω/Ω/°C)
500 ± 0.6 (α = 0.00385 Ω/Ω/°C) thin film
1000 ± 1.2 (α = 0.00385 Ω/Ω/°C) thin film
100 ± 0.1 Dual Element (α = 0.003924 Ω/Ω/°C)
100 ± 0.1 Dual Element (α = 0.00385 Ω/Ω/°C)
100 ± 0.12 Dual Element (α = 0.00385 Ω/Ω/°C) thin film
 
     SERVICE PARAMETER - Sinusoidal Vibration 20Hz to 2kHz
S
H
Standard construction (25 g wire-wound, 80 g thin film)
Heavy duty construction (up to 50 g) (single wire element only)
 
     PROBE LENGTH IN THERMOWELL
  Std. Const: 2" min, Heavy Duty: 3" min (see photo)
Specify length "A" (bore depth) in inches
 
     PROBE LAG HARDWARE - 1/2 NPT Fittings, stainless steel unless noted.
A
BX
EX
FX
GX
HX
JX

KX
Hex Nipple is 3/4" long standard. Specify as "A", (standard)
(Straight Nipple), specify X=1/8", 1/2", 1" + 1" increments
(Aluminum Union/Nipple Extension), specify X=min. 3" plus 1" increments
Same as EX (stainless union)
(Coupling/nipple extension), black iron, specify X=min. 3" + 1" increments
(Union/nipple extension), black iron, specify X=min. 3" + 1" increments
(Close nipple, galvanized unsealed parting coupling, nipple extension)
black iron, specify x=min. 1 1/2" + 1" increments (shortest “union”)
(Straight nipple) black iron, specify x=1/8", 1/2", 1", + 1" incr. (CREDIT)
 
     CONNECTION HEAD (see connection head table)
 
    NUMBER OF LEADS
A
B
C
D
E
Single element, 2 wires any length
Single element, 3 wires 36" or under in length
Single element, 4 wires 36" or under in length
Dual element, 2 wires per element
Dual element, 3 wires per element
 
     LEAD LENGTH (Specify in inches)
     (4" Standard)
21D
11
S
6
A
B
B
4
Typical Write-Up for 21D

LAG HARDWARE REFERENCE


PERFORMANCE SPECIFICATIONS

   
 

Features
Premium RTD Probe Assemblies with strain free
wire-wound sensing elements or economical
thin film sensing elements.

Operating Temperature Range
–196°C to 480°C (–320°F to 900°F) (SS Sheath)
Maximum Leadwire exit temperature: 260°C (500°F);
For higher temps, consult factory.

Resistance(Ohms @ 0 °C)
100.0 ± 0.1Ω (± 0.12Ω thin film)
200.0 ± 0.2Ω
500.0 ± 0.6Ω thin film
1000.0 ± 1.2Ω thin film

Temperature Coefficients
0.003924 Ω/Ω/°C (RdF Reference)
0.003850 Ω/Ω/°C (IEC/DIN grade)

Accuracy
0.25°C @ 0°C (32°F)
0.3°C @ 0°C (32°F) on IEC/DIN thin film

Stability
Less than 0.05°C shift per year
full span on wire elements,
–50°C to 300°C (–60°F to 575°F) span on thin films

     

Time Constant without Thermowell
Less than 6 sec. in water flowing at 3 ft. per sec.

Vibration
Sinusoidal 20Hz to 2kHz
Wire Element:25g Standard Construction
50g Heavy Duty Construction
Thin Film: 80g Standard Construction

Self Heating
35 mW/°F in water @ 3 ft/sec.

Insulation Resistance
500 Megohms minimum @ 100VDC @ 25°C (77°F)

Recommended Current
1mA maximum

Pressure Rating
3000PSI

Lead Materials
22 AWG nickel-plated stranded copper,
TFE Teflon® insulated

   

Teflon® is a registered trademark of the DuPont Corporation.


SCHEMATIC DIAGRAM

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LEAD REFERENCE