ST-120-3 3
1 Introduction
Electronic protection devices monitor the principal oper-
ating parameters and protect the compressor and the
system against abnormal operating conditions. The
protection devices SE-E* monitor the motor and dis-
charge gas temperature, rotation direction and phase
failure.
In addition to these functions, the SE-i1 monitors also
the cycling rate and the oil supply (oil level and oil flow).
During operation, numerous operating data of the com-
pressor can be tracked and evaluated via the integ-
rated interface using the BEST Software, for example,
the position in the application limits diagram. The data
are recorded and allow a specific diagnosis and optim-
ization of the compressor and system operation. For
further details, see Technical Information CT-110.
The protection devices OFC and SE-B2 are intended
for integration in the switch cabinet. They are used to
monitor the oil supply.
Only the protection devices SE-E2 and SE-i1 are
authorized for use with frequency inverters (FI).
This Technical Information provides an overview of all
BITZER protection devices for HS.-, CS.-, OS.- and
VSK screw compressors and a detailed description of
the following protection devices:
• SE-E1
• SE-E3
• SE-B2
• OFC
SE-B2 and OFC are used to monitor the oil circuit for
HS.- and OS.- screw compressors in connection with
the protection devices SE-E* (see chapter SE-B2, page
8 and see chapter OFC, page 8).
For the following protection devices, a separate Tech-
nical Information is available:
• SE-E2: Technical Information ST-122
•SE-i1: Technical Information CT-110
2 Safety
2.1 Authorized staff
All work done on the protection devices, compressors
and refrigeration systems may only be performed by
qualified and authorized staff who have been trained
and instructed accordingly. The local regulations and
guidelines will apply with respect to the qualification
and expertise of the specialists.
The protection devices have been built in accordance
with state-of-the-art methods and current regulations.
Particular importance was placed on user safety.
This Technical Information must be kept available near
the refrigeration system during the whole lifetime of the
protection device.
2.2 Residual risks
Compressors and electronic accessories may present
unavoidable residual risks. This is why any person
working on this device must carefully read this docu-
ment!
The following regulations shall apply:
• the relevant safety regulations and standards (e.g.
EN378, EN60204 and EN60335),
• generally accepted safety rules,
• EU directives,
• national regulations.
2.3 Safety references
are instructions intended to prevent hazards. Safety ref-
erences must be stringently observed!
NOTICE
Instructions on preventing possible damage to
equipment.
CAUTION
Instructions on preventing a possible minor haz-
ard to persons.
WARNING
Instructions on preventing a possible severe
hazard to persons.
DANGER
Instructions on preventing an immediate risk of
severe hazard to persons.
