Unlike traditional Pirani gauges, the sensor element in the

chip, allowing the measurements to be made in a very

decades below a standard Pirani sensor. The sensor

design minimizes the effects of convection, subsequently

the 901P can be mounted in any orientation without

compromising accuracy.

The Piezo is a differential pressure sensor, ensuring

correct atmospheric pressure measurement under varying

barometric pressure conditions. Piezo technology is a

direct pressure reading, allowing the measurement to be

gas independent. The Piezo sensor measures from -760 to

+760 Torr relative to atmospheric pressure.

The 901P has RS232, RS485, and EtherCAT digital

communication interfaces for setup of transducer

parameters and to provide real time pressure

measurement.

The 901P also has an analog pressure output of 1VDC/

decade that can be interfaced to external analog

equipment for pressure readout or control.

Other analog outputs and curves can be selected via the

digital user interface. A secondary optional analog output

is used to provide the differential pressure measurement.

The 901P has up to three mechanical relays which can be

used for process control, for example interlocking isolation

valves and vacuum pumps.

Each set point can be assigned either to the differential

piezo measurement or the combined absolute MicroPirani/

Piezo measurement. The 901P compact design

significantly reduces the amount of space occupied by a

vacuum gauge. This is particularly appealing to system

designers and allows for a more compact vacuum system.

Dimensional Drawings —

Note: Unless otherwise specified, dimensions are nominal values in inches (mm referenced).

Flange

A

NW 16 KF

1.93 (49.1)

NW 16 KF Ext

2.58 (65.6)

NW 25 KF

2.00 (50.9)

1/8'' NPT-M

3.50 (89.0)

3.20 (81.4)

3.24 (82.4)

CF 1.33’’

2.30 (58.5)

Flange

H

NW 16 KF

2.84 (73.39)

NW 16 KF Ext

3.52 (89.41)

NW 25 KF

3.23 (82.04)

1/8'' NPT-M

4.47 (113.54)

4.43 (112.52)

4.47 (113.54)

EtherCAT version

non-EtherCAT version

Pin

Rs232/485 15 pin sub-d

EtherCAT 15 pin sub-d

RJ45 EtherCAT In/OuT

1

RS485 (-)/RS232 transmit

NC

TX+

2

RS485 (+)/RS232 receive

NC

TX-

3

Power (+)

Input Power (+) 9 to 24 VDC

RX+

4

Power (-)

Power Return -

NC

5

Analog Output (+) abs.

Signal Output +

NC

6

Analog Output (-)

Signal Common

RX-

7

Relay #1 NO

NC

NC

8

Relay #1 Common

NC

NC

9

Relay #1 NC

NC

10

Relay #2 NC

NC

11

Relay #2 Common

NC

12

Relay #2 NO

NC

13

Relay #3 NC (or analog output diff)

NC

14

Relay #3 Common

NC

15

Relay #3 NO

Chassis Ground

PinOuts —

Three (3) set point relays and dual Aout, 15 pin D Subminiature and RJ45

EtherCAT IN/OUT Connectors