Pfeiffer Vacuum PTR 225 User manual

BG 5043 BEN / A
(
2016-10
)
OPERATING INSTRUCTIONS
Translation of the original instructions
PTR 225, PTR 225 S, PTR 237
Penning Gauge

2BG 5043 BEN / A (2016-10) PTR225_237.oi
In all communications with Pfeiffer Vacuum, please specify the information given
on the product nameplate.
Specimen nameplate
This document applies to products with part number
PT T13 148 300 (PTR 225, DN 25 ISO-KF)
PT T13 148 320 (PTR 225 S, DN 25 ISO-KF, with switching function)
PT T13 358 300 (PTR 237, DN 40 CF-F)
The part number (No) can be taken from the product nameplate.
We reserve the right to make technical changes without prior notice.
All dimensions in mm.
The references to diagrams, e.g. (4/5), consist of the fig. no. and the item no. in
that order.
The Penning Gauges PTR 225, PTR 225 S and PTR 237 have been designed for
vacuum measurement of in the pressure range of 1·10-9 to 1·10-2 mbar.
The Penning gauge PTR 225, PTR 225 S or PTR 237 is a compact active pressure
converter housing a Penning measurement system as well as the corresponding
operating electronics. They have been developed specifically for integration into
vacuum systems and offer a measurement range from 1·10-9 to 1·10-2 mbar.
The gauge is connected directly to the vacuum system through its DN 25 KF or
DN 40 CF flange.
The electrical connection is provided through a screened 8-pin FCC 68 connector.
Unpack the PTR 225, PTR 225 S or PTR 237 immediately after delivery, even if it
is to be installed at a later date.
Examine the packaging for any external damage. Completely remove all packaging
materials.
Retain the shipping container and the packaging materials in the event of
complaints about damage.
Check that the PTR 225, PTR 225 S or PTR 237 is complete and carefully examine
the gauges visually.
If any damage is discovered, report it immediately to the forwarding agent and in-
surer. If the damaged part has to be replaced, please get in touch with the orders
department.
Based on a supply voltage of 24 V the PTR 225, PTR 225 S or PTR 237 generates
the internal supply voltages required for operation of the integrated Penning mea-
surement system. The PTR 225, PTR 225 S or PTR 237 supplies a logarithmic
representation of the vacuum pressure by way of a voltage signal which ranges
from 0.66 V to 10 V. Moreover, the high tension generated in the PTR 225,
PTR 225 S or PTR 237 can be switched on and off by applying an external control
voltage or by connecting an external switch.
When the gas discharge in the Penning measurement system is ignited, the oper-
ating voltage is raised to 2.8 kV. After successful ignition, this voltage then drops to
1.6 kV thereby increasing the useful service life of the Penning measurement
system.
Product Identification
Validity
Intended Use
Description
Unpacking and Checking
Design and Function

BG 5043 BEN / A (2016-10) PTR225_237.oi 3
A status output indicates the two possible conditions of the Penning measurement
system:
1. not ignited (including high tension OFF) and
2. ignited (and pressure > 3·10-9 mbar).
A much improved ignition characteristic in the high vacuum range has been ob-
tained through the special design for the electrodes in the measurement system.
The PTR 225 S Penning gauge is equipped with an adjustable switching threshold.
The switching element is a relay. The status of the threshold is indicated by a LED.
•Penning gauge
•Replacement cathode plate of titanium
•Replacement ceramics disc
•3.5 mm jack plug (PTR 225 S only)
Scope of Delivery

4BG 5043 BEN / A (2016-10) PTR225_237.oi
Contents
Product Identification 2
Validity 2
Intended Use 2
Description 2
Unpacking and Checking 2
Design and Function 2
Scope of Delivery 3
Contents 4
1Safety 5
1.1 Symbols Used 5
1.2 Personnel Qualifications 5
1.3 General Safety Instructions 5
1.4 Liability and Warranty 5
2Technical Data 6
3Installation 8
3.1 Vacuum Connection 8
3.2 Electrical Connection 8
3.2.1 Power Supply 10
3.2.2 Switching on the High Tension 10
3.2.3 Measurement Signal Output 10
3.2.4 Status Output 11
3.2.5 Identification 11
3.2.6 Switching Threshold (PTR 225 S) 11
3.2.7 Monitor Output 12
4Operation 13
4.1 Operation 13
4.2 Measurement System Status Indication 14
4.3 Degassing 14
5Maintenance 15
5.1 The Electronics Assembly 15
5.2 Cleaning the Sensor 15
5.2.1 Detaching the Electronics Assembly 15
5.2.2 Disassembly of the Sensor 16
5.2.3 Cleaning the Individual Parts 16
5.2.4 Assembly of the Sensor 16
5.2.5 Assembly of the Electronics Assembly 17
6Troubleshooting 18
7Wearing Parts and Original Spare Parts 18
8Accessories 19
9Returning the Product 19
10 Disposal 20
Appendix 21
A: Relationship between output voltage and pressure (U = 0,4 V;
"not ignited") 21
B: Example for Connecting 22
C: Conversion Table 22
EU Declaration of Conformity 23
For cross-references within this document, the symbol (→XY) is used.

BG 5043 BEN / A (2016-10) PTR225_237.oi 5
1 Safety
DANGER
Information on preventing any kind of physical injury.
WARNING
Information on preventing extensive equipment and environmental damage.
Caution
Information on correct handling or use. Disregard can lead to malfunctions or
minor equipment damage.
Notice
Skilled personnel
All work described in this document may only be carried out by persons who
have suitable technical training and the necessary experience or who have been
instructed by the end-user of the product.
•Adhere to the applicable regulations and take the necessary precautions for the
process media used.
Consider possible reactions with the product materials (→6).
•Adhere to the applicable regulations and take the necessary precautions for all
work you are going to do and consider the safety instructions in this document.
•Before beginning to work, find out whether any vacuum components are conta-
minated. Adhere to the relevant regulations and take the necessary precautions
when handling contaminated parts.
Communicate the safety instructions to all other users.
Pfeiffer Vacuum assumes no liability and the warranty is rendered null and void if
the end-user or third parties
•disregard the information in this document
•use the product in a non-conforming manner
•make any kind of interventions (modifications, alterations etc.) on the product
•use the product with accessories not listed in the corresponding product docu-
mentation.
1.1 Symbols Used
Symbols for residual risks
1.2 Personnel Qualifications
1.3 General Safety
Instructions
1.4 Liability and Warranty

6BG 5043 BEN / A (2016-10) PTR225_237.oi
2 Technical Data
Measurement range 1·10-9 to 1·10-2 mbar
Measurement uncertainty in the range from 1·10-8 to 1·10-4 mbar
Deviation from the characteristic ±30 % of the displayed value
Average temperature coefficient of the
output span <0,5 % / K of the displayed value
Reproducibility <4 % of the displayed value
Measurement principle Cold cathode ionization according to
Penning
Supply voltage 14,5 to 36 V DC; typ. 24 V DC,
2 Vss
Power consumption <2 W
Protection IP 40
Flammability UL 94 - V 2
Status displays
Operation (POWER) orange LED
Ready to measure (ignited) READY green LED
Switching threshold (active)
(PTR 225 S only)
green LED
Measurement system detachable
Vacuum connection DN 25 KF or DN 40 CF
Degassing temperature see Section 4.3
Internal volume 21 cm3approx.
Materials in contact with the medium stainless steel; CrNi; AL2O3 ceramics;
NiFe; Ni; titanium
Overpressure tolerance 10 bar abs.
(The limits for the flange connections must be observed)
Operating voltage 1,6 kV (current limited to <0,5 mA)
Ignition voltage 2,8 kV (current limited to < 0,5 mA)
Signal output 0 to 10,6 V
Permissible load resistance Ra 10 k
Measurement signal 0,66 to 10,0 V
logarithmic 1,333 V / per decade
Status signal (not ignited) 0,4 V
Switching threshold Relay changeover contact
Adjustment range 1·10-9 to 1·10-3 mbar
Hysteresis ±30 % of the adjusted range
Rating DC 60 V, 0,5 A
Error status Resting contact when "not ignited";
"HV OFF" or "supply off"
General Data
Measurement System
Signal Output
Switching threshold
(PTR 225 S only)

BG 5043 BEN / A (2016-10) PTR225_237.oi 7
Input resistance RE: 10 kapprox.
High voltage cut-in with negative logic at
pin 7:
High voltage ON at U <2,5 V
High voltage OFF at U >4 V
or
High voltage cut-in with positive logic at
pin 8:
High voltage ON at U >12 V
High voltage OFF at U <7 V
Ready to measure High level (13,5 to 35 V, max.
50 mA)
Error (not ignited, HV off) 0 V
For this refer also to section 3.2.4.
Dimensions [mm]
Fig. 1 Dimensional drawing for PTR 225 and PTR 225 S
Weight 500 g approx.
Storage temperature range –20 °C to +70 °C
Climatic rating KWF to DIN 40040
Operating temperature range 10 °C to 50 °C
Max. rel. humidity of the ambient air (on 30
days per year, non-condensing) 70 %1) or 95 %2)
1) usable measurement range 10-2 to 10-9 mbar
2) usable measurement range 10-2 to 10-7 mbar
Control Inputs
Status Output
(Voltage output which is pro-
grammable control compatible)
Mechanical Data
Ambient Conditions

8BG 5043 BEN / A (2016-10) PTR225_237.oi
3 Installation
Please check by referring to the technical data whether or not your gauge is
suitable for your application.
The Penning gauge PTR 225, PTR 225 S or PTR 237 should preferably be
mounted flange down. Inclined installation is possible but the horizontal orientation
must not be exceeded.
Flange up installation is not permissible because under such circumstances
condensate may collect in the PTR 225, PTR 225 S or PTR 237. This will either
adversely affect the measurements, or the sensor itself may possibly be damaged.
The Penning gauge is equipped with a DN 25 KF or a DN 40 CF connection flange
which is used to connect the gauge to the mating connection flange on a vacuum
system with the aid of a centering ring and a clamping ring.
In the PTR 225, PTR 225 S or PTR 237 the cathode plate (7/5) also acts as a
baffle.
The supply voltage and the high voltage switching signal as well as the measure-
ment voltage signal are carried through the 8-way FCC 68 socket.
Fig. 2 Connection socket
The pinout is given in Fig. 2.
Pin Signal Designation on
the rear
Pin 1 Supply voltage 14,5 V to 36 V DC +24 V DC
Pin 2 0 V supply; used as the ground reference for the
supply and control signal voltages
COMMON
Pin 3 Pressure dependent logarithmic signal output SIGN 0 - 10 V
Pin 4 "PM gauge" identification (100 k) IDENT
Pin 5 Signal ground (use only for the pressure signal) SIGN COM
Pin 6 Status (ready to measure) STATUS
Pin 7 High tension "ON / OFF" (control input); Low active HV ON (L)
Pin 8 High tension "ON / OFF" (control input); High active HV ON (H)
Signal ground (Pin 5) and power supply ground (Pin 2) are internally linked. For
this also refer to the block diagram of Fig. 3.
An example of how to connect the PTR 225, PTR 225 S or PTR 237 is given in
Annex B.
3.1 Vacuum Connection
3.2 Electrical Connection

BG 5043 BEN / A (2016-10) PTR225_237.oi 9
Fig. 3 Block diagram PTR 225, PTR 225 S, PTR 237

10 BG 5043 BEN / A (2016-10) PTR225_237.oi
DANGER
The Penning gauge PTR 225, PTR 225 S or PTR 237 may only be
connected to supply units or measuring instruments which meet the
requirements of mains isolated extra-low voltages (PELV) and
VDE 0100.
The Penning gauges PTR 225, PTR 225 S or PTR 237 is capable of operating off
supply voltages ranging from 14.5 V to 36 V. A supply voltage of 24 V DC is recom-
mended.
The power supply must be connected to Pin 1 (+) and Pin 2 (power supply ground).
The high voltage may be switched on either through Pin 7 using negative logic or
Pin 8 using positive logic.
In each case Pin 2 must be used as the reference potential.
Pin 7 switches the high voltage on when
•contact is established with Pin 2 or
•a voltage of less than 2.5 V is present with reference to Pin 2.
Pin 7 switches the high voltage off when
•there is no contact with Pin 2 (open input) or
•a voltage greater than 4 V is present with reference to Pin 2.
Pin 8 switches the high voltage on when
•contact is established with Pin 1 (supply voltage) or
•a voltage greater than 12 V is present with reference to Pin 2.
Pin 8 switches the high voltage off when
•there is no contact with Pin 1 (open input) or
•a voltage of less than 7 V is present with reference to Pin 2.
Operation of the PTR 225, PTR 225 S or PTR 237 in the pressure range above
10-2 mbar will cause the accumulation of contaminations and will thus reduce
service life. For this reason, the high tension should only be switched on or off
when the pressure has dropped to the 10-2 to 10-3 mbar range.
The high tension may also be switched on or off directly by the output signal pro-
vided by a Pirani gauge TTR 91 S / TTR 96 S. Thus the Penning gauge can be
switched on or off automatically at a pressure of approximately 5·10-3 mbar.
The PTR 225, PTR 225 S or PTR 237 supplies a defined output signal ranging
from 0.66 V to 10 V at Pin 3 with reference to Pin 5 which is signal ground. For this
also refer to Table 1 in Annex A.
Table 1 has been included to clarify the relationship between the output voltage
and the pressure.
The measurement signal provided by the Penning gauge depends on the type of
gas. The values stated in Table 1 apply to nitrogen and air. For other gases,
corresponding correction factors must be used which are available from Pfeiffer
Vacuum upon request.
3.2.1 Power Supply
3.2.2 Switching on the High
Tension
3.2.3 Measurement Signal
Output

BG 5043 BEN / A (2016-10) PTR225_237.oi 11
When the gauge is ready to measure, this is indicated via the status output.
Status Status signal at Pin 6 (with respect
to Pin 2)
High voltage OFF 0 V
High voltage ON
(not yet ignited) 0 V
High voltage ON
at p < 3·10-9 mbar
0 V
High voltage ON
at p > 3·10-9 mbar
High (13.5 - 32 V, depending at
p > 3·10-9 mbar on the supply vol-
tage (50 mA max.)
When the pressure drops below 3·10-9 mbar, the status signal remains HIGH.
For the purpose of identifying the connected type of gauge and the pressure range,
the Penning gauge is equipped with an identification resistor (R = 100 k) between
Pin 4 and Pin 2. This resistor may be sensed by connected operating or control
units so that these can automatically adapt.
The built-in switching threshold may be adjusted through potentiometer (4/2) in the
range between 1·10-3 -1·10-9 mbar.
To adjust the threshold remove the cap (4/2) and use a screwdriver to adjust the
threshold to the desired level.
In order to check the adjustment, a voltmeter may be connected to the monitor
output (4/1) (see Section 3.2.7 and Table 1 in the Annex).
The threshold switch is a floating relay (changeover contact) which may be
accessed via pluggable screw terminals (4/4). When the pressure drops below the
adjusted threshold, a green LED (4/3) comes on.
In the case of a fault (i.e. discharge not present) or if the supply voltage has been
switched off the relay contacts return to their rest position.
Key to Fig. 4
1 Monitor output
2 Potentiometer for adjustment
of the switching threshold
3 LED (green)
4 Connector
Pin 1 Ground
Pin 2 Normally open relay
contact
Pin 3 Center relay contact
Pin 4 Normally closed contact
Fig. 4 Penning gauge PTR 225 S
3.2.4 Status Output
3.2.5 Identification
3.2.6 Switching Threshold
(PTR 225 S)

12 BG 5043 BEN / A (2016-10) PTR225_237.oi
The monitor output (4/1) is accessible through a 3.5 mm jack socket so that the
measurement signal and the trigger setting may be measured. The stereo jack plug
which is included with the instrument may be used to connect a voltmeter, for
example. For this also refer to Fig. 5.
Value for the trigger threshold
Fig. 5 Jack plug for the monitor output
3.2.7 Monitor Output
Measurement signal

BG 5043 BEN / A (2016-10
)
4 Oper
a
4.1 Oper
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PTR225_237.oi
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o
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o
n.
t
he high tensi
o
ccessful igniti
Y
LED (6/2) wi
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a
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s
urement sig
n
supply voltag
high tension
h
s
urement sig
n
supply voltag
high tension
h
gas discharg
e
pressure is o
v
s
urement sig
n
DANGER
n
sion which is
the Penning
g
o
r the gauge b
m
oving the ga
u
e
n inadverten
t
s
mitter - front
v
y
voltage to th
o
n on via the
h
on and at a p
r
l
l come on.
a
dy to make
m
missing.
n
al 0 V
e is present.
h
as not been
s
n
al 0 V
e is present.
h
as been swi
t
e
has been st
a
v
er 3·10
-9
mb
a
n
al 0,66 V
dangerous w
h
g
auge. You m
efore starting
u
ge from the c
t
ly coming in t
o
v
ie
w
K
1
2
e gauge. The
h
igh tension s
w
r
essure > 3·1
0
easurements
.
s
witched on.
c
hed on.
a
rted.
a
r
w
hen touched i
ust always s
w
any work on
t
c
onnection fla
n
o
contact wit
h
K
ey to Fig. 6:
1
LED "PO
W
2
LED "RE
A
orange "PO
W
s
witching inpu
t
0
-9
mbar the
a
.
s applied to t
h
w
itch off the s
u
t
he gauge (ev
n
ge) so as to
a
h
the high ten
s
W
ER" (orange
)
A
DY" (green)
W
ER" LED (6/
1
t
. See Sectio
n
a
dditional gre
e
13
h
e
u
pply
en
a
void
s
ion.
)
1
)
n
3.2.2.
e
n or

14 BG 5043 BEN / A (2016-10) PTR225_237.oi
In the case of the Penning method of measurement one only may draw conclu-
sions as to proper functioning while the gauge is in the measurement mode, i.e.
when the gas discharge is running.
Trouble-free operation ("READY" LED (6/2) is on, status output HIGH) is marked
by the presence of a pressure dependent signal starting at a pressure of about
3·10-9 mbar up to the range limit of 1·10-2 mbar. When the pressure drops
< 3·10-9 mbar this status is also maintained.
When the “READY” LED (6/2) is not on, status output 0 V:
Cause 1: When the high voltage was switched on the pressure was below
p <3·10-9 mbar.
Cause 2: No ignition of the gas discharge, even if the power supply voltage is
present, the high tension has been switched on and a pressure
between about 3·10-9 mbar and 1·10-2 mbar.
WARNING
Before baking out the sensing cell you must detach the electronics
assembly from the sensing cell. The electronics assembly may be
damaged when exceeding a temperature of 70 °C.
Before baking out, you must make sure that an aluminum edged seal
(PTR 225 / PTR 225 S) or a copper seal (PTR 237) is used as the
flange seal.
The Penning gauge PTR 225, PTR 225 S or PTR 237 are equipped with all-metal
sensing cells so that any outgassing caused by polymer seals is entirely avoided.
After having detached the electronics (refer to Section 5.2.1) from the sensing cell,
the outgassing rate of the sensing cell may be reduced considerably by baking out,
so that the accuracy of the measurements in the range below 1·10-6 mbar is im-
proved.
When using the gauge chiefly in the UHV range (< 10-8 mbar) it is recommended to
remove the cathode plate. This helps to reduce the surface area of the surfaces
which may release gas.
How to proceed in order to detach the electronics assembly is described in Section
5.2 (cleaning of the sensor).
Permissible bake out temperatures:
Sensing cell of the PTR 225 / 225 S: 150 °C
(with aluminum edged seal)
Sensing cell of the PTR 237: 350 °C
4.2 Measurement System
Status Indication
4.3 Degassing

BG 5043 BEN / A (2016-10) PTR225_237.oi 15
5 Maintenance
DANGER
DANGER: contaminated parts
Contaminated parts can be detrimental to health and environment.
Before you begin to work, find out whether any parts are contami-
nated. Adhere to the relevant regulations and take the necessary
precautions when handling contaminated parts.
Caution
Caution: vacuum component
Dirt and damages impair the function of the vacuum component.
When handling vacuum components, take appropriate measures to
ensure cleanliness and prevent damages.
Caution
Caution: dirt sensitive area
Touching the product or parts thereof with bare hands increases the
desorption rate.
Always wear clean, lint-free gloves and use clean tools when working
in this area.
The electronics assembly of the Penning gauge PTR 225, PTR 225 S or PTR 237
does not require any maintenance.
DANGER
A high tension which is dangerous when touched is applied to the
sensor in the Penning gauge. You must always switch off the supply
voltage for the gauge before starting any work on the gauge (even
when removing the gauge from the connection flange) so as to avoid
injury when inadvertently coming in to contact with the high tension.
In order to detach the electronics assembly and the magnet assembly (7/1) you
must loosen the two cross head screws which can be accessed through two holes
in the rear of the gauge by turning these by about 1.5 turns.
Then the electronics assembly and the magnet assembly (7/1) may be pulled off
from the sensor housing.
The magnet assembly (7/1) may drop down during the pulling off pro-
cess.
5.1 The Electronics
Assembly
5.2 Cleaning the Sensor
5.2.1 Detaching the
Electronics Assembly

16
5.2.2
5.2.3
5.2.4
Disasse
m
Sensor
Cleaning
Parts
Assembl
y
m
bly of the
the Indivi
d
y
of the Se
n
T
(
7
H
1
2
3
F
I
n
s
t
b
b
I
f
s
a
c
e
t
a
T
d
W
r
e
M
W
(
7
d
ual
n
so
r
he sensor co
n
7
/2) and the c
a
H
ow to disass
e
) Use a pair
o
) Use a pair
o
the pliers t
o
) Detach the
ig. 7 Sensor
Do
n
n
the case of
s
t
eel wool or si
low clean wit
h
e
removed b
y
possible, the
a
me should b
e
e
ramics prote
a
mination.
he sensor is
r
e
scribed in S
e
W
hen insertin
g
e
mains betwe
e
M
oreover, ma
k
W
hen insertin
g
7
/2) must not
b
n
sists of the v
a
a
thode plate
(
e
mble:
o
f tweezers t
o
o
f pliers to pu
l
o
and fro a littl
ceramics dis
c
n
ot damage t
h
s
evere conta
m
i
milar and the
n
h
oil-free pres
s
y
blowing thes
e
cathode plat
e
e done for th
e
ction disc (7/
3
r
eassembled i
e
ction 5.2.2.
g
the anode ri
n
en the wings
o
k
e sure that th
g
the cathode
b
e bent. Ther
e
a
cuum housi
n
(
7/5). See Fig.
o
pull the cath
o
l
l the anode ri
n
e
.
c
(7/3) from th
h
e sealing sur
f
m
ination, the i
n
n
subjected t
o
s
urized air or
n
e
out of the h
o
e
(7/5) should
e
anode ring (
7
3
) which prote
c
n the reverse
n
g (7/4) you
m
o
f the ignition
e anode ring
i
p
late (7/5) int
o
e
fore insert sl
o
n
g, the anode
7.
o
de plate (7/5
)
n
g out from t
h
e
current fee
d
K
e
1
2
3
4
5
6
f
aces of the v
a
n
side of the h
o
o
further clean
n
itrogen. Any
o
using.
be replaced
b
7
/4) with the i
g
c
ts the curren
order as for d
m
ust make sur
e
aid (7/2) and
s lying snug
o
o
the housing
o
wly and car
e
BG 5043 BEN /
A
ring (7/4) wit
h
) out of the s
e
h
e housing; fo
r
d
- through.
e
y to fig. 7:
Magnet ass
e
Ignition aid
ceramics di
s
Anode ring
Cathode pla
Sensor hou
s
flange
a
cuum flange
.
o
using may b
e
ing with alco
h
possibly pres
b
y a new cath
o
g
nition aid (7/
2
n
t feed-throug
h
d
isassembly
w
e
that a clear
a
the wall of th
e
o
n the cerami
c
the wings of
t
e
fully.
A
(2016-10) PTR225_237
h
ignition aid
e
nsor.
r
this move
e
mbly
s
c
t
e
s
ing with
.
e
cleaned wit
h
h
ol. Finally
ent flakes will
o
de plate. Th
e
2
) and the
h
against con
-
w
hich is
a
nce of 1 mm
e
housing.
c
s disc.
t
he ignition ai
d
.oi
h
e
-
d

BG 5043 BEN / A (2016-10) PTR225_237.oi 17
How to proceed:
1) Place the magnet assembly on the sensor.
2) Push the electronics assembly over the magnet assembly and the sensor, and
turn slightly as required until the correct orientation between electronics
assembly and sensor has been found. When the electronics assembly has
been placed as required, the black magnet housing is fully surrounded by the
housing of the PTR 225, PTR 225 S or 237.
3) Retighten the cross head screws at the rear of the gauge.
5.2.5 Assembly of the
Electronics Assembly

18 BG 5043 BEN / A (2016-10) PTR225_237.oi
6 Troubleshooting
Problem Possible cause Correction
No LED is on. Supply voltage is missing.
The "POWER" LED (6/1)
is on, the "READY" LED
(6/2) is not on.
High tension has not been ac-
tivated. Pressure has dropped
below < 3·10-9mbar.
The gas discharge has not
ignited.
Sensing cell not properly con-
nected to the electronics as-
sembly (e.g. after mainte-
nance).
Missing anode ring (e.g. after
maintenance).
The measurement signal
is always greater than
10 V even if the pressure
is much lower than
10-2 mbar.
Short circuit in the sensing
cell.
Clean the sensing
cell. For this refer to
section 5.2.
During pumpdown the
measurement signal re-
mains at some level al-
though the pressure is
dropping.
Contamination within the sen-
sing cell.
Replace the sen-
sing cell.
7 Wearing Parts and Original Spare Parts
When ordering spare parts, always indicate:
•all information on the product nameplate
•description and ordering number according to the spare parts list
Ordering number
Maintenance set, consisting of:
Cathode plate of titanium (5 pcs.)
Ceramics disc (5 pcs)
Gauge
PT 120 030 -T
Repair set kit, consisting of:
Anode ring with ignition aid
PT 120 031 -T
Replacement sensor (DN 25 KF),
complete with magnet assembly (PR 25)
PT 120 032 -T
Replacement sensor (DN 40 CF-F),
complete with magnet assembly
PT 120 033 -T

BG 5043 BEN / A (2016-10) PTR225_237.oi 19
8 Accessories
Ordering number
10 m long connection cable,
with two FCC 68 plugs, screened PT 448 450 -T
Ordering number
Clamping ring for metal seals DN 25 ISO-KF 110BSD025
Aluminum edged seal, aluminum, annealed, DN 25 ISO-KF 110ZSK025
9 Returning the Product
WARNING
WARNING: forwarding contaminated products
Products returned to Pfeiffer Vacuum for service or repair should, if
possible, be free of harmful substances (e.g. radioactive, toxic, caustic
or microbiological). Otherwise, the type of contamination must be de-
clared.
Adhere to the forwarding regulations of all involved countries and for-
warding companies and enclose a completed contamination declara-
tion (form under www.pfeiffer-vacuum.com).
Products that are not clearly declared as "free of harmful substances" are de-
contaminated at the expense of the customer.
Products not accompanied by a duly completed declaration of contamination are
returned to the sender at his own expense.
For overpressure operation and
degassing:

20 BG 5043 BEN / A (2016-10) PTR225_237.oi
10 Disposal
DANGER
DANGER: contaminated parts
Contaminated parts can be detrimental to health and environment.
Before beginning to work, find out whether any parts are contami-
nated. Adhere to the relevant regulations and take the necessary pre-
cautions when handling contaminated parts.
WARNING
WARNING: substances detrimental to the environment
Products or parts thereof (mechanical and electric components,
operating fluids etc.) can be detrimental to the environment.
Dispose of such substances in accordance with the relevant local
regulations.
After disassembling the product, separate its components according to the
following criteria:
Contaminated components (radioactive, toxic, caustic or biological hazard etc.)
must be decontaminated in accordance with the relevant national regulations,
separated according to their materials, and disposed of.
Such components must be separated according to their materials and recycled.
Separating the components
Contaminated components
Other components