Ashcroft N Data sheet

231

Load Limitations 4-20mA Output

Loop Resistance Ω

0 10 12 20 24 30 36 40

0

250

500

750

1000

1250

1091

OPERATING

REGION

545

Electronic Pressure Switches,
Watertight or Explosion-Proof
Enclosure, N-Series

Special features:

• Ashcroft

®

K Series polysilicon thin
film pressure sensor (transducer)
for long, stable life (minimum 1
million cycles at rated load)

• Setpoint repeatability of 0.5% of
range

• Choice of watertight, NEMA 4 or
explosion-proof NEMA 7/9, IP66
enclosures for safety and reliability

• Pressure setpoints to 20,000 psi

• Deadbands adjustable between

0.1% and 95% of nominal range

• Multi-turn potentiometers make
setpoint and deadband adjust­ments easy

1 - FUNCTION

NPA - Single setpoint with adjustable deadband

2 - ENCOSURE

N4 NEMA 4, IP66, watertight

N7 NEMA 7/9, IP66, explosion proof

3 - OUTPUT

D SPDT Relay 10A, 250 Vac
10A, 30 Vdc

I SPDT Relay and 10A, 250 Vac
current output 10A, 30 Vdc
and 4-20mA

4 - POWER REQUIREMENTS

Code Power Supply

L 110 Vac, 50/60 Hz
C 24 Vdc
V 250 Vac, 50/60 Hz

5 - PRESSURE CONNECTIONS

Code Description

S01 1⁄8 NPT male
S02 1⁄4 NPT male
S03 1⁄8 NPT female
S04 1⁄4 NPT female
S05 7⁄16 -20 SAE-male
S06 1⁄2 NPT male
S07 1⁄4 AMINCO-female
S08 7⁄16 -20 SAE-J514-female

• Status lights indicate switch state

• Continuous power assures opera­tion first time and every time even
after years of inactivity

Ideal for pressure alarm, shutdown,
control on:

• Machine tools

• Injection molding machines

• Presses

• Pumps

• Hydraulic systems

• Turbines and compressors

NEMA 7 (N7) Model Shown

• Most process applications

6 - OPTIONS

Code Description

XEA External adjustment (N4 only)

7 - STANDARD PRESSURE RANGES

Range Setpoint

(1)

Proof Burst

psi Limits psi psi psi

60 3-60 120 480
100 5-100 200 800
200 10-200 400 1600
300 15-300 600 2400
500 25-500 1000 4000
750 35-750 1500 6000
1000 50-1000 2000 8000
2000 100-2000 4000 16,000
3000 150-3000 4500 15,000
5000 250-5000 7500 25,000
7500 375-7500 9000 22,500

(2)

10,000
15,000
20,000

(1) Switch setpoint is adjustable throughout these limits.
(2) Pressure connection S07 only on these ranges.

500-10,000 12,000 30,000

(2)

750-15,000 18,000 45,000

(2)

1000-20,000 24,000 60,000

NOTES:

Temperature Specifications (70°F ref.)
–20°F to 160°F ambient and process
Setpoint shift of up to 2% of range per 50°F change can
be expected

OPTIONAL TRANSMITTER SPECIFICATIONS

PERFORMANCE CHARACTERISTICS
Accuracy Class (F.S.): 1%

Nonlinearity
Terminal Point* ±0.7%
B.F.S.L. ±0.4%
Hysteresis ±0.2%
Nonrepeatability ±0.07%
Interchangeability ±1.0%
*Includes hysteresis

Stability: ±0.5% F.S./year
Durability: 108 cycles 20/80% F.S. with negligible

performance change

Response Time: Less than 5msec
ENVIRONMENTAL CHARACTERISTICS

Temperature Limits:

Storage –65/+250°F
Operating –20/+180°F
Compensated –20/+160°F

Thermal Coefficients (70°F ref.):

Accuracy Zero and Span
1% ±0.040% F.S./°F

ELECTRICAL SPECIFICATIONS
Output Signal: Supply Voltage:

4-20mA (2 wire) 12-36 Vdc unregulated

Reverse wiring protected.
Zero Offset: ±1.0%F.S.

Load Limitations 4-20mA Output

Loop Resistance (

Ω)

TO ORDER THIS N-SERIES PRESSURE SWITCH:

Select: NPA N4 D L S02 XEA 100#

1. Function:

2. Body:

3. Electrical Output:

4. Power Requirements:

5. Pressure Port:

6. Options (see table 6):

7. Pressure Range (see table 7):

Consult factory for guidance in product selection
Phone [phone], Fax [phone] or
visit our web site at www.ashcroft.com

V

= 12V+ [.022A*(RL)]

min

*Includes a 10% safety factor
RL = RS + RW
RL = Loop Resistance (ohms)
RS = Sense Resistance (ohms)
RW = Wire Resistance (ohms)