Operation; Environment And Mounting; Power Sources; Battery Charger Zg 011 4 - BRUEL & KJAER 4912 Instruction Manual

3. OPERATION
3.1. ENVIRONMENT AND MOUNTING
The Portable Stroboscope Type 491 2 may be used over a wide temperature range,
-1 0° to + 55° ( 14° to 1 31 °F). The permissible upper limit of relative humidity is 90%,
non-condensing.
The carrying handle of the 491 2 incorporates a standard tapped hole for tripod moun-
ting (3/8-in Whitworth). It may be mounted on the portable tripod UA 0587 or any other
similar support. It may also be stood upright on its base provided the supporting surface
is reasonably level.
3.2. POWER SOURCES
The Type 491 2 may be powered from its internal rechargeable batteries, or from a sui-
table external source . The pointer of the BATTERY LEVEL indicator leans to the right
(thus: /) when the battery voltage is sufficient to power the 491 2. This condition will oc-
cur after a relatively short period of charging. Consequently the indicator cannot be used
as a guide to whether or not the battery is fully charged. The only way to be sure that
the battery is fully charged is to keep the 491 2 on charge for the period of time speci-
fied below. The indicator will show whether or not the battery has received some
charge; it will also show eventually whether the battery needs to be replaced by indicat-
ing that the battery voltage falls to below the usable level after a shorter operating time
than when the Stroboscope was new. The battery can undergo approximately a thou-
sand charge/discharge cycles before its performance deteriorates, however. Replace-
ment is a service operation. Note that the true battery condition is indicated by the BAT-
TERY LEVEL indicator only when the charging source is switched off or disconnected.
3.2.1. Battery Charger ZG 0113
6
The simplest method of recharging the batteries is to use the battery charger ZG 0113
supplied (Fig.4, Chapter 1 ). Before this can be done, the battery charger must be fitted
with a suitable plug for connection to a single-phase AC mains supply . For mains vol-
tages between 1 00 V and 1 30 V, connect the supply between the blue and black conduc-
tors in the unterminated cable attached to the battery charger . For voltages between
200V and 240V, connect it between the blue and brown conductors. The unused con-
ductor should be cut back or insulated.The 7-pin DIN plug attached to the other cable on
the battery charger is then plugged into the POWER INPUT socket on the 4912 . Recharg-
ing completely exhausted batteries takes about 10 hours with the ZG 0113 . No harm
will result from prolonging the charging time. However, if the instrument is used infre-
quently, it should not be left on permanent charge as this practice tends to shorten bat-
tery life.