Fairchild TT7800, TA7800, TD7800, T7800 Series Installation, Operation And Maintenance Instructions

FAIRCHILD T7800 EXTENDED RANGE

MINIATURE ELECTRO-PNEUMATIC TRANSDUCER

Installation, Operation and Maintenance Instructions

Figure 1. Model T7800 Extended Range Transducer Identification Number System.

GENERAL INFORMATION

The Model T7800 Series of Electro-Pneumatic Trans­ducer converts a DC input signal to a linearly proportional
pneumatic output pressure.

SPECIFICATIONS

1

Specifications (continued)

HAZARDOUS AREA CLASSIFICATION

FM Approval (continued):

Non-Incendive: (4-20 mA and voltage input units)
(TDFI7800, TAFI7800, TDFN7800, TAFN7800)

Class I, Division 2, Groups A, B, C and D;
Class II, Division 2, Groups F, and G;
Class III, Division 2;
NEMA 4X Enclosure;
Te mperature Code T4.

(TTFI7800, TRFI7800, TTFN7800, TRFN7800)

Class I, Division 2, Groups A, B, C and D;
Te mperature Code T4.

CSA (Canadian Standards Association) Approvals:

Intrinsically Safe: (4-20 mA only)
(TDCI7800, TACI7800)

Class I, Division 1, Groups C and D;
Class II, Division 1, Groups E, F, and G;
Type 4 Enclosure;
Rated 4-20 mA, 30 VDC Maximum;
Te mperature Code T6.

(TTCI7800, TRCI7800)

Class I, Division 1, Groups C and D;
Te mperature Code T6.

Approvals are valid when connected through a Shunt
Zener Diode Safety Barrier meeting the following para­metric requirements:

System
Type 1:

System
Type 2:

System
Type 3:

Single Channel Polarized Rated: 28.5V Max.
300 Ohm Min.

Dual Channel Polarized Rated: 28.5V Max. 300
Ohm Min. and 10V Max. 50 Ohm Min.

Dual Channel Polarized Rated: 28.5V Max. 300
Ohm Min. and 28V Diode return per channel.

Division 2 Approvals: (4-20 mA only)
(TDCI7800, TTCI7800, TRCI7800)

Class I, Division 2, Groups A, B, C and D;
Rated 4-20 mA, 30 VDC Maximum;
Te mperature Code T6.

(TACI7800)

Class I, Division2, Groups A, B, C and D;
Class II, Division 2, Groups E, F, and G;
Type 4 Enclosure;
Rated 4-20 mA, 30 VDC Maximum;
Te mperature Code T6.

FM (Factory Mutual) Approvals:

Intrinsically Safe: (4-20 mA only)
(TDFI7800, TAFI7800)

Class I, Division 1, Groups C and D;
Class II, Division 1, Groups E, F, and G;
Class III, Division 1,Fibers;
NEMA 4X Enclosure;
Te mperature Code T4.

(TTFI7800, TRFI7800)

Class I, Division 1, Groups C and D;
Te mperature Code T4.

Entity Parameters

1

Vmax
Imax

1

Vmax = Maximum Voltage

2

Imax = Maximum Current

=
=

30 VDC
200 mA

2

Ci
Li

3

4

3

=

4

0 F

=

0 mH

Ci = Capacitance

Li = Inductance

ATEX Approvals:
Intrinsically Safe: (4-20 mA only)
(TAEI7800, TDEI7800, TTEI7800, TREI7800)

II 1G (T4)
EEx ia IIB, T4 (-200 C to +720 C Ambient).

(TAEI7800, TDEI7800)

IP65 Enclosure.

Transducer Parameters

1

Umax

2

Imax

1

Umax = Maximum Voltage

2

Imax = Maximum Current

(Ui)

(Ii)

=

28 V

=

100 mA

3

Wmax

4

(Ci)

Ceq

5

Leq

(Li)

3

Wmax = Maximum Power

4

Ceq = Capacitance

5

Leq = Inductance

2

(Wi)

=
=
=

0.7 W
0
0

INSTALLATION

The Model T7800 can be mounted directly onto a flat
surface using two 10-32 Screws. For more information,
see Figure 2. “TA7800 Outline Dimensions”.

The Model T7800 is supplied with a Mounting Kit EA­16799-1 for Panel or Wall Mounting and a Mounting Bracket
Kit EA-16893-1 for Din Rail Mounting. For more informa­tion, see Figure 3. on page 3 and Figure 7. on page 5.

An Optional Mounting Kit EA-19254-1 is available when
installing the unit on a 2" pipe. For more information, see
Figure 8. on page 5.

NOTE:

The TR7800 Transducer is designed for use
with the TR Rack Kit. Physically, it is the same
as the TT7800 (Terminal Block) Unit except
that the terminal block has been rotated to the
rear. For more information, see Figure 6.
“TR7800 Outline Dimensions” on page 4.

Figure 2. TA7800 Outline Dimensions.

Figure 3. Mounting Kit EA-16799-1. (Included with Unit)

ATEX Directive - Special Conditions for Safe Use:

The enclosure is manufactured from aluminum alloy. In rare cases, ignition sources due to impact and friction sparks could occur.

This shall be considered when the equipment is installed in locations that specifically require Group II, category 1G equipment

3

.

Installation (continued)

5 15/64

133.0

1/4 NPT

Outlet

Port (2)

(typical)

1 33/64

38.7

++

V

Z

OUT

OUT

Z

_

V

S

S

IN

1/4 NPT
Inlet
Port (2)
(typical)

IN

Figure 4. TT7800 Outline Dimensions.

90 Alternating
Positions

S

21/4

57.1

27/32

21.5

4 57/64

124.3

15/16

33.3

127/64

36.2

4 21/32

118.1

5 15/64

133.0

1/4 NPT

Outlet

Port (2)

(typical)

1/4 NPT

Outlet

Port (2)

(typical)

OUT

OUT

1 33/64

38.7

_

++

V

VS

OUT

OUT

IN

1/4 NPT
Inlet
Port (2)
(typical)

IN

Figure 5. TD7800 Outline Dimensions.

21/4

57.1

Vent

IN

1/4 NPT
Inlet
Port (2)
(typical)

IN

111/16

42.9

27/32

21.5

457/64

124.3

Figure 6. TR7800 Outline Dimensions.

4

Installation (continued)

Figure 7. Din Rail Mounting Kit EA-16893. (Included with Unit)

Figure 8. Optional Mounting Kit EA-19254-1. (Sold Separately)

5

Pneumatic Connections

Electric Connections

Clean all pipelines to remove dirt and scale before instal­lation.

Apply a minimum amount of pipe compound to the male
threads of the fitting only. Do Not use teflon tape as a
sealant. Start with the third thread back and work away
from the end of the fitting to avoid the possibility of
contaminating the transducer. Install the transducer in
the air line.

The inlet and outlet ports, in the lower valve body, are
labeled on the ends of the transducer. Tighten connec­tions securely. Avoid undersized fittings that will limit the
flow through the transducer and cause a pressure drop
downstream. For more information, see Figure 2.
“Outline Drawing” on page 3.

NOTE:

Instrument quality air, per ISA Standards S7.3­1981, is required. Use a filter to remove dirt
and liquid in the air line ahead of the trans­ducer for correct performance. If an air line
lubricator is used, it MUST be located down­stream, beyond the transducer.

The user is responsible for insuring that the
environment in which the unit will be in­stalled, and the operating gas, are compatible
with the materials in the transducer.

Make connections to the Terminal Block, Conduit Connec­tor or the DIN Connector as shown below in Figure 9.
“Electrical Connections”.

Wiring in Hazardous Areas

Wiring in hazardous areas should be performed in accor­dance with the table 1. and any local codes that apply.

Table 1. Hazardous Location Wiring Practices.

Country

U.S.

Agency

FM

Code

ANSI/ISA RP 12.6

ANSI/NFPA 70
Canada
Europe

CSA
ATEX

CED Part 1

EN 50 039

Intrinsically Safe Connections

Refer to the latest revision of the indicated drawing.

Table 2. Intrinsically Safe Connections.

Underwriting Group Drawing Number

FM (Factory Mutual)
CSA (Canadian Standards)
ATEX

EC-18970
EC-18971
EC-18972

Figure 9. Electrical Connections.

6

CALIBRATIONS / ADJUSTMENTS

SPLIT RANGE OPERATION

Equipment Required for Calibration:

• Pneumatic Supply capable of delivering up to 150 psig.

• Current Supply capable of delivering up to 60 mA.

• Pressure Gage capable of a digital readout up to 150

psig with an accuracy of .1%.

• Digital Volt Meter capable of a readout up to 60 mA with
an accuracy of .02%.

The following adjustments are provided:

Full Range Operation
Lo/Hi Span
Forward/Reverse Mode
Calibration - Zero and Span
Split Range Operation
Damping Adjustments

FULL RANGE OPERATION

Lo/Hi Span Adjustment

1.

Set the Lo/Hi Span Jumper to the Hi position for 0-30
psig, 0-60 or 0-120 psig output range. For more
information, see Table 3. “Full Range Operation” on
page 8.

Lo/Hi Span Adjustment

1.

Set the Lo/Hi Span switch to the Lo position for 0-15
psig, 15-30 psig, 0-30 psig, 30-60 psig, 0-60 psig, or
60-120 psig, output range. For more information,
see Table 4. “Split Range Operation” on page 8.

Forward Acting Mode Adjustment

2.

Set Fwd/Rev Mode Jumper to the Forward position.

• Forward Acting Calibration - Zero

3.

Apply the minimum input signal and adjust the Zero
screw for minimum output pressure.

• Forward Acting Calibration - Span

4.

Apply the maximum input signal and adjust the Span
screw for maximum output pressure.

5.

Repeat steps 3-4 until the desired output range is
obtained.

Reverse Acting Mode Adjustment

NOTE:

6.

DO NOT reverse the input leads.

Set Fwd/Rev Mode Jumper to the Reverse position.

Forward Acting Mode Adjustment

2.

Set Fwd/Rev Mode Jumper to Forward position.

• Forward Acting Calibration - Zero

3.

Apply the minimum input signal and adjust the Zero
screw for minimum output pressure.

• Forward Acting Calibration - Span

4.

Apply the maximum input signal and adjust the Span
screw for maximum output pressure.

5.

Repeat steps 3-4 until the desired output range is
obtained.

Reverse Acting Mode Adjustment

NOTE:

6.

DO NOT reverse the input leads.

Set Fwd/Rev Mode Jumper to the Reverse position

• Reverse Acting Calibration - Zero

7.

Apply the maximum input signal and adjust the Zero
screw for minimum output pressure.

• Reverse Acting Calibration - Span

8.

Apply the minimum input signal and adjust the Span
screw for maximum output pressure.

• Reverse Acting Calibration - Zero

7.

Apply the maximum input signal and adjust the Zero
screw for minimum output pressure.

• Reverse Acting Calibration - Span

8.

Apply the minimum input signal and adjust the Span
screw for maximum output pressure.

9.

Repeat steps 7-8 until the desired output range is
obtained.

Additional Adjustments

• Damping Adjustment

The Damping Adjustment is used so that the transducer
can be tuned for optimum response and stability in a
particular application.

For best performance start Damping Adjustment at
maximum adjustment (fully clockwise). Gradually turn
counterclockwise until slight oscillation occurs and then
turn back clockwise until oscillation is minimized. For
more information, see Figure 10. “T7800 Calibration
Configuration”

Turn Damping Adjustment clockwise to increase

1.

damping function.

9.

Repeat steps 7-8 until the desired output range is
obtained.

Turn Damping Adjustment counterclockwise to

2.

decrease damping function.

7

Calibrations / Adjustments (continued)

Table 3. Full Range Operation.

Input

4-20 mA, 0-5, 1-5,
0-10 & 1-9 VDC

HI SPAN SETTING
(Current & Voltage)

J7 Jumper

Adjustment

Output

psig BAR (kPa)

0-30 0-2 0-200 HI
0-60 0-4 0-400 HI
0-120 0-8 0-800 HI

Zero

J7

Span

Position

Jumper

H

Table 4. Split Range Operation.

Input

4-20 mA, 0-5, 1-5,
0-10 & 1-9 VDC

1

Split Range Output.

J7

Jumper

Output

psig

0-15 0-1 0-100 LO

15-30 1-2 100-200 LO

0-30 0-2 0-200 LO

30-60 2-4 200-400 LO

0-60 0-4 0-400 LO

60-120 4-8 400-800 LO

BAR

1

1

1

1

1

1

1

1

1

LO SPAN SETTING

(Current & Voltage)

1

1

1

L

J1 Jumper

FORWARD ACTING

OPERATION

(Current Unit)

Span

Position

(kPa)

1
1
1

1

1

1

DAMPING
ADJUSTMENT

Decrease

Damping

Function

Span

Adjustment

Increase
Damping
Function

J1

REVERSE ACTING

OPERATION

(Current Unit)

C

B

A

D

J1

J1

B

A

J1

FORWARD ACTING
OPERATION
(Voltage Unit)

C

B

A

REVERSE ACTING
OPERATION
(Voltage Unit)

D

C

A

B

D

C

D

Figure 10. T7800 Calibration Configuration.

8

Table 5. T7800 Transducer Components.

Item

Qty.

Description

1
2
3
4
5
6
6
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
22
23
24
25
26
27
28
29
30
31

Cover, Machining

1

Screw

2

Screw

2

1

2

3

4

1

1

1

1

1

1

2

5

1

1

Gasket

1

Nozzle Body Assembly

1

Orifice Assembly

1

Orifice Assembly

1

Orifice Assembly

1

Spring

1

Disk

1

Diaphragm

1

Spacer Ring

1

Diaphragm Assembly

1

Foam Block

1

Valve Body Assembly

1

Screw

3

Pintle

1

Spring, PIntle

1

O-Ring

1

Plug

1

Screw

2

Diaphragm

1

Spacer Ring

1

Diaphragm Assembly

1

Diaphragm Assembly

1

Spring

1

Foam Block

1

Valve Body Assembly

1

Screw

3

Pintle

1

Spring, Pintle

1

O-Ring

1

Plug

1

Screw

2

1

For All Service Kits.

2

EA-19267-4 Service Kit Components Only.

0-30 psig, [0-2.0 BAR], (0-200 kPa)

3

EA-19267-5 Service Kit Components Only.

0-60 psig, [0-4.0 BAR], (0-400 kPa)

4

EA-19267-6 Service Kit Components Only.

0-120 psig, [0-8.0 BAR], (0-800 kPa)

5

EA-19267-5 & EA-19267-6 Service Kit

Figure 11. Exploded Drawing.

9

MAINTENANCE

TROUBLE-SHOOTING

To clean the Orifice, use the following procedure:

Shut off the valve that is supplying air to transducer.

1.
It is not necessary to remove the Transducer
from the air line.

Remove the Orifice Assembly (6) from the unit. For

2.

more detailed information see Figure 11. “Exploded
Drawing” on page 9.

Clean with alcohol and dry with compressed air.

3.

NOTES:

Parts must be completely dry before reassem­bling.

If the standard maintenance procedure does
not correct the trouble, install Service Kit.

Table 6. Trouble-Shooting.

Problem

No Output

Solution (check)

Supply Pressure
Clogged Orifice

Leakage

Low or Improper
Span Adjust

Connections

Zero and Span Adjust
Supply Pressure Low
Output Leakage

Erratic Operation

DC Signal
Loose Wires or Connections
Liquid in Air Supply

WARNING:

Failure of Transducer could result in out­put pressure increasing to supply pres­sure possibly causing personal injury or
damage to equipment.

LEGAL NOTICE:

The information set forth in the foregoing Installation, Operation and Maintenance Instructions shall not be
modified or amended in any respect without prior written consent of Fairchild Industrial Products Company.
In addition, the information set forth herein shall be furnished with each product sold incorporating Fairchild's
unit as a component thereof.

IS-50T7800E
Litho in USA
Rev. H 04/05