3570 Series
3
Table 1. Specifications
Available Configurations
See the positioner type number descriptions given
above.
Input Signal
(1)
Standard Ranges: 3 to 15 psig (0.2 to 1.0 bar) or
6 to 30 psig (0.4 to 2.0 bar)
Optional Ranges: As desired, within the limits of
the bellows
Split Ranges: Use one-half of either standard
range when two control valves are operated by one
output signal form a single control device
Output Signal
(1)
Type: Pneumatic pressure as required to maintain
the correct valve stem position and seat load
Action: Field-reversible between direct and reverse
Resolution
(1)(2)
0.2% of instrument pressure span
Repeatability
(1)(2)
0.3% of total stroke or instrument pressure span
Frequency Response
(1)(2)
See figure 5
Pressure Connections
Vent: 3/8-inch NPT
All others: 1/4-inch NPT
Pressure Indications
Type 3570C and 3570CP Positioners: Tire valves
accept standard pressure gauge chucks (gauges
not supplied)
All Other Types: Gauges supplied per table 2
Bellows Pressure Rating
Standard Bellows: 50 psig (3.4 bar)
Optional Bellows: 90 psig (6.2 bar)
Supply Pressure
Maximum: 150 psig (10.4 bar)
Minimum: 35 psig (2.4 bar)
Steady-State Air Consumption
(3)
20 scfh (0.54 normal m
3
/h) with 100 psig (6.9 bar)
supply pressure
Operative Ambient Temperature Limits
(1)(2)
With Nitrite O-Rings and Diaphragms: –30 to
160°F (–34 to 71°C)
With Fluoroelastomer O-Rings and Polyacrylate
Diaphragms (Optional): 0 to 220°F (–18 to 104°C)
Options
Type SS-52 clip-on chuck (with or without gauge)
for Type 3570C positioners; restrictor (high-fre-
quency filter for bellows)
Approximate Weight
6 pounds (2.7 kg) without optional mounting bracket
or actuator/valve assembly
1. These terms are defined in ISA Standard S51.1:1979.
2. For a Type 3570 or 3570C positioner mounted on a Type 470 or 480 actuator. Values do not apply to other constructions or actuator-valve combinations.
3. Scfh at 60°F, 14.7 psia (m
3
/h at 0°C, 1.01325 bar, absolute).
Table 2. Pressure Indications
PRESSURE
NUMBER OF
GAUGES SUPPLIED
ST
ANDARD GAUGE
MONITORED
Two-Relay
Positioner
One-Relay
Positioner
RANGE
(1)
Positioner
input signal
pressure
1 1
0-30 psi/0-0.2 MPa/0-2 bar or
0-60 psi/0-0.4 Mpa/0-4 bar
Cylinder
(relay output)
pressure
2 1 0-160 psi/0-1.1 MPa/0-1
1 bar
1. For gauges marked in other units and ranges, consult your Fisher sales
representative or sales office.
The Type 3576 positioner is bracket-mounted to the
actuator yoke. Actuator stem position feedback is pro-
vided through a wire from the actuator-valve stem con-
nector.
Table
3. Action Under Normal Operating Conditions
POSITIONER
DESIRED PISTON MOTION
(1)
ACTION
Down Up
Direct-acting
Increasing input signal
pressure to bellows
Decreasing input signal
pressure to bellows
Reverse-acting
Decreasing input signal
pressure to bellows
Increasing input signal
pressure to bellows
1. Supply pressure is routed through relays to piston.
Type 3577 — Pneumatic valve positioner that is simi-
lar to Type 3576 positioner with the relay output pres-
sure piped to the underside of the actuator diaphragm
on reverse-acting pneumatic diaphragm actuators.
Specifications
Specifications for the 3570 Series positioners are
listed in table 1.
To Next Page
Loading...
