| AC voltage measurement |
| Range |
500 V |
| Resolution |
0.1 V |
| Accuracy 45 Hz – 66 Hz |
0.8% + 3 |
| Input impedance |
360 kΩ |
| Overload protection |
660 V rms |
| Continuity testing (RLO) |
| Range (autoranging) |
20 Ω / 200 Ω / 2000 Ω |
| Resolution |
0.01 Ω / 0.1 Ω / 1 Ω |
| Open Circuit Voltage |
>4 V |
| Insulation resistance measurement (RISO) |
| Test voltages |
50-100-250-500-1000 V |
| Accuracy of tTest voltage (at rated test current) |
+10%, -0% |
| Test voltage |
50 V
100 V
250 V
500 V
1000 V |
| Insulation resistance range |
20 MΩ /50 MΩ
20 MΩ / 100 MΩ
20 MΩ / 200 MΩ
20 MΩ / 200 MΩ / 500 MΩ
20 MΩ / 200 MΩ / 1000 MΩ |
| Resolution |
0.01 MΩ / 0.1 MΩ
0.01 MΩ / 0.1 MΩ
0.01 MΩ / 0.1 MΩ
0.01 MΩ / 0.1 MΩ / 1 MΩ
0.01 MΩ / 0.1 MΩ / 1 MΩ |
| Test current |
1 mA @ 50 kΩ
1 mA @ 100 kΩ
1 mA @ 250 kΩ
1 mA @ 500 kΩ
1 mA @ 1 MΩ |
| Loop and line impedance (ZI) |
| Range |
10 Ω / 0.001 Ω / High current mΩ mode |
| Resolution |
0.01 Ω / 0.1 Ω / 1 Ω |
| Prospective earth fault current, PSC test |
| Range |
1000 A / 10 kA (50 kA) |
| Resolution |
1 A / 0.1 kA |
| Computation |
Prospective earth fault current (PEFC) or Prospective short circuit current (PSC) determined by dividing measured mains voltage by measured loop (L-PE) resistance or line (L-N) resistance, respectively. |
| RCD testing, RCD types tested |
| RCD Type |
AC¹
G²,S³ |
| Model 1664 |
A, AC, B5, S |
| Notes |
¹Responds to AC
²General, no delay
³Time delay
4Responds to pulsed signal
5Responds to smooth DC signal |
| Tripping speed test (ΔT) |
| Current settings¹ |
10-30-100-300-500-1000 mA – VAR
10-30-100 mA |
| Multiplier |
x ½, x 1
x 5 |
| Measurement range |
RCD Type G |
310 ms
50 ms |
| RCD Type S |
510 ms
160 ms |
| Notes |
¹1000 mA type AC only
700 mA maximum type A in VAR mode
VAR mode not available for type B. |
| RCD/FI-Tripping Current Measurement/Ramp Test (IΔN) |
| Current range |
30% to 110% of RCD rated current¹ |
| Step size |
10% of IΔN² |
| Dwell time |
Type G |
300 ms/step |
| Type S |
500 ms/step |
| Measurement accuracy |
±5% |
| Specified trip current ranges (EN 61008-1) |
50% to 100% for Type AC
35% to 140% for Type A (>10 mA)
35% to 200% for Type A (≤10 mA)
50% to 200% for Type B
²5% for Type B |
| Notes |
¹30% to 150% for Type A IΔN > 10 mA
30% to 210% for Type A IΔN = 10 mA
20% to 210% for Type B |
| Earth Resistance Test (RE) |
| Range |
200 Ω / 2000 Ω |
| Resolution |
0.1 Ω / 1Ω |
| Frequency |
128 Hz |
| Output Voltage |
25 V |
| Phase Sequence Indication |
| Icon |
 Phase Sequence indicator is active. |
| General Specifications |
| Size (L x W x H) |
10 x 25 x 12.5 cm |
| Weight (incl. batteries) |
1.3 Kg |
| Battery size, quantity |
Type AA, 6 ea. |
| Sealing |
IP-40 |
| Safety |
Complies with EN61010-1 Ed 2.0 (2001-02), UL61010, ANSI/ISA –s82.02.01 2000 and CAN/CSA c22.2 No. 1010 2nd edition |
| Overvoltage |
CAT III / 500V; CAT IV 300V |
| Performance |
EN61557-1 to EN61557-7 Second Edition and EN61557-10 Second Edition |