5
5) MAINTENANCE
WARNING
To avoid electrical shock, disconnect test leads from live circuits before opening the case. Do not operate with
open case.
Cleaning and Storage
Periodically wipe the case with a damp cloth and mild detergent; do not use abrasives or solvents. If the meter is
not to be used for periods of longer than 60 days, remove the battery and store it separately
Trouble Shooting
If the instrument fails to operate, check battery, leads, etc., and replace as necessary. Double check operating
procedure as described in this user’s manual
If the instrument voltage-resistance input has subjected to high voltage transient (mostly caused by lightning or
switching surge to your system) by accident or abnormal conditions of operation, the series fusible resistors will be
blown off (become high impedance) like fuses to protect the user and the instrument. Most measuring functions
through this input will then be open circuit. The series fusible resistors and the spark gaps should then be replaced
by qualified technician. Refer to the LIMITED WARRANTY section for obtaining warranty or repairing service.
Battery replacement
If the meter starts up with persistent resetting display or with low battery icon turns on, replace the battery
ASAP. The meter uses one 3V coin battery IEC-CR2032.
Before opening the case bottom, make sure the meter is switched off to avoid abrupt power reset to a running
meter system. Disconnect test leads from live circuits. Loosen the screw from the case bottom. Lift the end of the
case bottom nearest the input test leads until it unsnaps from the case top. Replace the battery. Observe battery
polarities with positive (+) faces up (towards the case bottom). Replace the case bottom, and ensure that the snap
on the case top (near the LCD side) is engaged. Re-fasten the screw.
Note for
Models 27s, 25s
& 25a
battery replacement:
*
Models 27s, 25s
& 25a
use micro-controller (like a computer) to run the meter system. WHEN THE METER IS
POWER-ON, intermittence battery power failure (fast intermittence battery contact interval in the order of
millisecond) may cause the meter reset/re-startup abnormally. Simply press and hold the SELECT button for
approximately 6 seconds to master reset the system if such a situation occurs.
6) SPECIFICATION
GENERAL SPECIFICATIONS
Display & Update Rate:
Model 22s
: 3-3/4 digits 4000 counts; Updates 3 per second nominal
Models
25a,
25s & 27s
: 3-5/6 digits 6000 counts; Updates 5 per second nominal
Operating Temperature:
0
o
C ~ 40
o
C
Relative Humidity:
Maximum relative humidity 80% for temperature up to 31
o
C decreasing linearly to 50%
relative humidity at 40
o
C
Altitude:
Operating below 2000m
Storage Temperature:
-20
o
C ~ 60
o
C, < 80% R.H. (with battery removed)
Temperature Coefficient:
Nominal 0.15 x (specified accuracy)/
o
C @ (0
o
C ~ 18
o
C or 28
o
C ~ 40
o
C), or otherwise
specified
Sensing:
Average sensing
Pollution Degree:
2
Safety:
Meets
IEC/UL/EN61010-1 Ed. 3.0, IEC/EN61010-2-030 Ed. 1.0, IEC/EN61010-2-033 Ed. 1.0,
IEC/UL/EN61010-031 Ed. 1.1 and CAN/CSA-C22.2 No. 61010-1-12 Ed. 3.0
Transient Protection:
4kV lightning surge (1.2/50
s)
