Dynamic Uninterrupted
Power Supplies
Application Note
Mission critical business operations cannot af-
ford even the slightest of downtime, let alone
an extended power outage. To keep information
technology, telecommunicaons, and factory oor
and call centre operaons running smoothly, busi-
nesses have to take a close look at their power
infrastructure to identify vulnerabilities and take
acon to prevent costly downme.
A key component of an effective power infra-
structure is the UPS
system. UPS systems
provide a rst line of
defence against un-
expected downtime
and load loss, and
offer various levels
of redundancy, com-
munications and
interoperability with
other power equip-
ment.
There are different
systems on offer
today to solve the
problems linked with the connuity of power sup-
ply.
One of our customers, a leading dynamic UPS
system manufacturer from Belgium, has one such
system that provides a power soluon to ensure
uninterrupted, connuous and condioned power
supply to mission crical processes.
According to the Project Engineer, when there is
a failure at the main power grid, the switching of
the Dynamic UPS from “Normal Mode” to “Emer-
gency Mode” is achieved by the
switching of the D1 and D2 relays
as shown on the next page in Fig-
ure 3.
As such, measuring the switch-
ing conditions of these 2 relays
during maintenance becomes an
important task in order to ensure
that the Dynamic UPS is able to
quickly support the loads during a
mains failure situaon.
Analysing the Data
Figure 2 on the next page shows an example of
the data measured and recorded with the Hioki
Memory HiCorder MR8880-20.
From the logic waveform data recorded by
MR8880-20 for the D1 and D2 relays, the delay
timing between these 2 relays can be captured
and the duration of the chattering of the relays
can also be determined.
MEMORY HiCORDER Case Study
Figure 1: Dynamic UPS
© 2012 HIOKI E.E. CORPORATION
A_AP_MR8880-20appnoteE02
One-touch easy load printer option is
indispensable for factory maintenance
By using the cursor function on
the MR8880-20, the customer
was able to quickly determine
all the parameters related to
the switching of the D1 and D2
relays and easily print out the
results using the MR8880-20
printer. Any faulty relays can be
immediately identified and re-
placed ensuring the funconality
of the Dynamic UPS.
Professional Tool
The customer had commented
that the Hioki Memory HiCorder
MR8880-20 is such a versatile
tool that not only can it record
logic signals, but is also able to
record voltage waveforms of
up to 600V and current signals
simultaneously. This feature
allows them to perform more
tasks in the future should the
need arises.
The Hioki MR8880-20 Memory
HiCorder was chosen for exactly
these reasons.
Figure 2: Actual Logic switching
of D1 and D2 relays
Figure 3: MR8880-20 Measuring D1 and D2
switching relays
© 2012 HIOKI E.E. CORPORATION
A_AP_MR8880-20appnoteE02
■ All information correct as of April 2012.
■ Contents are subject to change without notice.